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c-decl.c overhaul (1/3) Refactor duplicate_decls
- From: "Zack Weinberg" <zack at codesourcery dot com>
- To: gcc-patches at gcc dot gnu dot org
- Date: Sat, 10 Jan 2004 17:18:36 -0800
- Subject: c-decl.c overhaul (1/3) Refactor duplicate_decls
This is patch 1 of 3 in a series which eventually will result in
fixing all the bugs related to bad scoping of identifier bindings in
the C front end (at least 12267, 12336, 12373, 12391, 12560, 12934,
13129). This one is just laying groundwork: I have restructured
duplicate_decls so that it is comprehensible and modifiable. It
should be noted that I made it somewhat pickier in the process: I
removed two special cases where the type compatibility rules were
relaxed for the sake of K+R code, and I made certain warnings
unconditional where formerly they appeared only with -pedantic. Apart
from the above special cases, I do not believe that any more code is
outright rejected. I also arranged always to indicate the location of
the previous decl, which fixes some long-standing expected failures in
the test suite.
Some weird special cases remain - one for a pseudo-K+R construct that
I expect is still fairly common, one for Objective C's not-really-
builtin builtins, and a few more.
Part of the point of this patch is that I need to make changes of
behavior to duplicate_decls, so I'm getting the changes of form out of
the way now; part of the point is to get all the testsuite tweaks out
of the way in advance.
Bootstrapped i686-linux. Patches 2 and 3 in this series will need
more extensive testing; in particular, I am looking for help testing
on powerpc-darwin.
zw
* c-decl.c (duplicate_decls): Break apart into...
(diagnose_arglist_conflict, validate_proto_after_old_defn)
(locate_old_defn, diagnose_mismatched_decls, merge_decls):
... these new functions. Restructure for comprehensibility.
Remove various archaic special cases. Always report the
location of the previous declaration when a diagnostic is issued.
(redeclaration_error_message): Fold into diagnose_mismatched_decls.
(match_builtin_function_types): Delete unnecessary forward declaration.
testsuite:
* gcc.dg/Wshadow-1.c, gcc.dg/attr-noinline.c, gcc.dg/decl3.c
* gcc.dg/redecl-1.c, gcc.dg/visibility-7.c, gcc.dg/wtr-static-1.c
* gcc.dg/noncompile/20020220-1.c, objc.dg/method-1.m:
Update dg-error regexps.
===================================================================
Index: c-decl.c
--- c-decl.c 7 Jan 2004 19:39:58 -0000 1.466
+++ c-decl.c 11 Jan 2004 01:08:44 -0000
@@ -306,9 +306,6 @@ tree static_ctors, static_dtors;
static struct c_scope *make_scope (void);
static void pop_scope (void);
-static tree match_builtin_function_types (tree, tree);
-static int duplicate_decls (tree, tree, int, int);
-static int redeclaration_error_message (tree, tree);
static tree make_label (tree, location_t);
static void bind_label (tree, tree, struct c_scope *);
static void implicit_decl_warning (tree);
@@ -755,12 +752,12 @@ pushtag (tree name, tree type)
TYPE_CONTEXT (type) = DECL_CONTEXT (TYPE_STUB_DECL (type));
}
-/* Subroutine of duplicate_decls. Allow harmless mismatches in return
+/* Subroutine of compare_decls. Allow harmless mismatches in return
and argument types provided that the type modes match. This function
return a unified type given a suitable match, and 0 otherwise. */
static tree
-match_builtin_function_types (tree oldtype, tree newtype)
+match_builtin_function_types (tree newtype, tree oldtype)
{
tree newrettype, oldrettype;
tree newargs, oldargs;
@@ -795,121 +792,227 @@ match_builtin_function_types (tree oldty
return build_type_attribute_variant (trytype, TYPE_ATTRIBUTES (oldtype));
}
-/* Handle when a new declaration NEWDECL
- has the same name as an old one OLDDECL
- in the same binding contour.
- Prints an error message if appropriate.
-
- If safely possible, alter OLDDECL to look like NEWDECL, and return 1.
- Otherwise, return 0.
-
- When DIFFERENT_BINDING_LEVEL is true, NEWDECL is an external declaration,
- and OLDDECL is in an outer scope and should thus not be changed. */
-
-static int
-duplicate_decls (tree newdecl, tree olddecl, int different_binding_level,
- int different_tu)
+/* Subroutine of diagnose_mismathed_decls. Check for function type
+ mismatch involving an empty arglist vs a nonempty one and give clearer
+ diagnostics. */
+static void
+diagnose_arglist_conflict (tree newdecl, tree olddecl,
+ tree newtype, tree oldtype)
{
- int types_match = comptypes (TREE_TYPE (newdecl), TREE_TYPE (olddecl),
- COMPARE_STRICT);
- int new_is_definition = (TREE_CODE (newdecl) == FUNCTION_DECL
- && DECL_INITIAL (newdecl) != 0);
- tree oldtype = TREE_TYPE (olddecl);
- tree newtype = TREE_TYPE (newdecl);
- int errmsg = 0;
-
- if (DECL_P (olddecl))
- {
- if (TREE_CODE (newdecl) == FUNCTION_DECL
- && TREE_CODE (olddecl) == FUNCTION_DECL
- && (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl)))
+ tree t;
+
+ if (TREE_CODE (olddecl) != FUNCTION_DECL
+ || !comptypes (TREE_TYPE (oldtype), TREE_TYPE (newtype), COMPARE_STRICT)
+ || !((TYPE_ARG_TYPES (oldtype) == 0 && DECL_INITIAL (olddecl) == 0)
+ ||
+ (TYPE_ARG_TYPES (newtype) == 0 && DECL_INITIAL (newdecl) == 0)))
+ return;
+
+ t = TYPE_ARG_TYPES (oldtype);
+ if (t == 0)
+ t = TYPE_ARG_TYPES (newtype);
+ for (; t; t = TREE_CHAIN (t))
+ {
+ tree type = TREE_VALUE (t);
+
+ if (TREE_CHAIN (t) == 0
+ && TYPE_MAIN_VARIANT (type) != void_type_node)
{
- if (DECL_DECLARED_INLINE_P (newdecl)
- && DECL_UNINLINABLE (newdecl)
- && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
- /* Already warned elsewhere. */;
- else if (DECL_DECLARED_INLINE_P (olddecl)
- && DECL_UNINLINABLE (olddecl)
- && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
- /* Already warned. */;
- else if (DECL_DECLARED_INLINE_P (newdecl)
- && ! DECL_DECLARED_INLINE_P (olddecl)
- && DECL_UNINLINABLE (olddecl)
- && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
- {
- warning ("%Jfunction '%D' redeclared as inline",
- newdecl, newdecl);
- warning ("%Jprevious declaration of function '%D' "
- "with attribute noinline", olddecl, olddecl);
- }
- else if (DECL_DECLARED_INLINE_P (olddecl)
- && DECL_UNINLINABLE (newdecl)
- && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
- {
- warning ("%Jfunction '%D' redeclared with attribute noinline",
- newdecl, newdecl);
- warning ("%Jprevious declaration of function '%D' was inline",
- olddecl, olddecl);
- }
+ inform ("a parameter list with an ellipsis can't match"
+ "an empty parameter name list declaration");
+ break;
}
- DECL_ATTRIBUTES (newdecl)
- = (*targetm.merge_decl_attributes) (olddecl, newdecl);
+ if (c_type_promotes_to (type) != type)
+ {
+ inform ("an argument type that has a default promotion can't match"
+ "an empty parameter name list declaration");
+ break;
+ }
}
+}
- if (TREE_CODE (newtype) == ERROR_MARK
- || TREE_CODE (oldtype) == ERROR_MARK)
- types_match = 0;
+/* Another subroutine of diagnose_mismatched_decls. OLDDECL is an
+ old-style function definition, NEWDECL is a prototype declaration.
+ Diagnose inconsistencies in the argument list. Returns TRUE if
+ the prototype is compatible, FALSE if not. */
+static bool
+validate_proto_after_old_defn (tree newdecl, tree newtype, tree oldtype)
+{
+ tree type, parm;
+ int nargs;
+ /* Prototype decl follows defn w/o prototype. */
+
+ for (parm = TYPE_ACTUAL_ARG_TYPES (oldtype),
+ type = TYPE_ARG_TYPES (newtype),
+ nargs = 1;
+ ;
+ parm = TREE_CHAIN (parm), type = TREE_CHAIN (type), nargs++)
+ {
+ if (TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == void_type_node
+ && TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
+ {
+ /* End of list. */
+ warning ("%Jprototype for '%D' follows non-prototype definition",
+ newdecl, newdecl);
+ return true;
+ }
- /* New decl is completely inconsistent with the old one =>
- tell caller to replace the old one.
- This is always an error except in the case of shadowing a builtin. */
+ if (TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == void_type_node
+ || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
+ {
+ error ("%Jprototype for '%D' with different number of arguments "
+ "follows non-prototype definition", newdecl, newdecl);
+ return false;
+ }
+ /* Type for passing arg must be consistent
+ with that declared for the arg. */
+ if (! comptypes (TREE_VALUE (parm), TREE_VALUE (type),
+ COMPARE_STRICT))
+ {
+ error ("%Jprototype for '%D' with incompatible argument %d "
+ "follows non-prototype definition", newdecl, newdecl, nargs);
+ return false;
+ }
+ }
+}
+
+/* Subroutine of diagnose_mismatched_decls. Report the location of DECL,
+ first in a pair of mismatched declarations, using the diagnostic
+ function DIAG. */
+static void
+locate_old_decl (tree decl, void (*diag)(const char *, ...))
+{
+ if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
+ ;
+ else if (DECL_INITIAL (decl))
+ diag (N_("%Jprevious definition of '%D' was here"), decl, decl);
+ else if (C_DECL_IMPLICIT (decl))
+ diag (N_("%Jprevious implicit declaration of '%D' was here"), decl, decl);
+ else
+ diag (N_("%Jprevious declaration of '%D' was here"), decl, decl);
+}
+
+/* Subroutine of duplicate_decls. Compare NEWDECL to OLDDECL.
+ Returns true if the caller should proceed to merge the two, false
+ if OLDDECL should simply be discarded. As a side effect, issues
+ all necessary diagnostics for invalid or poor-style combinations.
+ If it returns true, writes the types of NEWDECL and OLDDECL to
+ *NEWTYPEP and *OLDTYPEP - these may have been adjusted from
+ TREE_TYPE (NEWDECL, OLDDECL) respectively. */
+
+static bool
+diagnose_mismatched_decls (tree newdecl, tree olddecl,
+ tree *newtypep, tree *oldtypep)
+{
+ tree newtype, oldtype;
+ bool pedwarned = false;
+ bool warned = false;
+
+ /* If we have error_mark_node for either decl or type, just discard
+ the previous decl - we're in an error cascade already. */
+ if (olddecl == error_mark_node || newdecl == error_mark_node)
+ return false;
+ oldtype = TREE_TYPE (olddecl);
+ newtype = TREE_TYPE (newdecl);
+ if (oldtype == error_mark_node || newtype == error_mark_node)
+ return false;
+
+ /* Two different categories of symbol altogether. This is an error
+ unless OLDDECL is a builtin. OLDDECL will be discarded in any case. */
if (TREE_CODE (olddecl) != TREE_CODE (newdecl))
{
- if (TREE_CODE (olddecl) == FUNCTION_DECL
- && DECL_BUILT_IN (olddecl))
+ if (TREE_CODE (olddecl) != FUNCTION_DECL || !DECL_BUILT_IN (olddecl))
{
- /* If you declare a built-in or predefined function name as static,
- the old definition is overridden,
- but optionally warn this was a bad choice of name. */
- if (!TREE_PUBLIC (newdecl))
+ error ("%J'%D' redeclared as different kind of symbol",
+ newdecl, newdecl);
+ locate_old_decl (olddecl, error);
+ }
+ else if (TREE_PUBLIC (newdecl))
+ warning ("%Jbuilt-in function '%D' declared as non-function",
+ newdecl, newdecl);
+ else if (warn_shadow)
+ warning ("%Jshadowing built-in function '%D'",
+ newdecl, newdecl);
+ return false;
+ }
+
+ if (!comptypes (oldtype, newtype, COMPARE_STRICT))
+ {
+ if (TREE_CODE (olddecl) == FUNCTION_DECL && DECL_BUILT_IN (olddecl))
+ {
+ /* Accept harmless mismatch in function types.
+ This is for the ffs and fprintf builtins. */
+ tree trytype = match_builtin_function_types (newtype, oldtype);
+
+ if (trytype && comptypes (newtype, trytype, COMPARE_STRICT))
+ oldtype = trytype;
+ else
{
- if (warn_shadow)
- warning ("%Jshadowing built-in function '%D'",
- newdecl, newdecl);
+ /* If types don't match for a built-in, throw away the
+ built-in. No point in calling locate_old_decl here, it
+ won't print anything. */
+ warning ("%Jconflicting types for built-in function '%D'",
+ newdecl, newdecl);
+ return false;
}
- else
- warning ("%Jbuilt-in function '%D' declared as non-function",
- newdecl, newdecl);
+ }
+ else if (TREE_CODE (olddecl) == FUNCTION_DECL
+ && DECL_SOURCE_LINE (olddecl) == 0)
+ {
+ /* A conflicting function declaration for a predeclared
+ function that isn't actually built in. Objective C uses
+ these. The new declaration silently overrides everything
+ but the volatility (i.e. noreturn) indication. See also
+ below. FIXME: Make Objective C use normal builtins. */
+ TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
+ return false;
+ }
+ /* Permit void foo (...) to match int foo (...) if the latter is
+ the definition and implicit int was used. See
+ c-torture/compile/920625-2.c. */
+ else if (TREE_CODE (newdecl) == FUNCTION_DECL && DECL_INITIAL (newdecl)
+ && TYPE_MAIN_VARIANT (TREE_TYPE (oldtype)) == void_type_node
+ && TYPE_MAIN_VARIANT (TREE_TYPE (newtype)) == integer_type_node
+ && C_FUNCTION_IMPLICIT_INT (newdecl))
+ {
+ pedwarn ("%Jconflicting types for '%D'", newdecl, newdecl);
+ /* Make sure we keep void as the return type. */
+ TREE_TYPE (newdecl) = newtype = oldtype;
+ C_FUNCTION_IMPLICIT_INT (newdecl) = 0;
+ pedwarned = true;
}
else
{
- error ("%J'%D' redeclared as different kind of symbol",
- newdecl, newdecl);
- error ("%Jprevious declaration of '%D'", olddecl, olddecl);
+ error ("%Jconflicting types for '%D'", newdecl, newdecl);
+ diagnose_arglist_conflict (newdecl, olddecl, newtype, oldtype);
+ locate_old_decl (olddecl, error);
+ return false;
}
-
- return 0;
}
- /* For real parm decl following a forward decl, return 1 so old decl
- will be reused. Only allow this to happen once. */
- if (types_match && TREE_CODE (newdecl) == PARM_DECL
- && TREE_ASM_WRITTEN (olddecl) && ! TREE_ASM_WRITTEN (newdecl))
+ /* Redeclaration of a type is a constraint violation (6.7.2.3p1),
+ but silently ignore the redeclaration if either is in a system
+ header. (Conflicting redeclarations were handled above.) */
+ if (TREE_CODE (newdecl) == TYPE_DECL)
{
- TREE_ASM_WRITTEN (olddecl) = 0;
- return 1;
+ if (DECL_IN_SYSTEM_HEADER (newdecl) || DECL_IN_SYSTEM_HEADER (olddecl))
+ return true; /* allow OLDDECL to continue in use */
+
+ error ("%Jredefinition of typedef '%D'", newdecl, newdecl);
+ locate_old_decl (olddecl, error);
+ return false;
}
- /* The new declaration is the same kind of object as the old one.
- The declarations may partially match. Print warnings if they don't
- match enough. Ultimately, copy most of the information from the new
- decl to the old one, and keep using the old one. */
-
- if (TREE_CODE (olddecl) == FUNCTION_DECL && DECL_BUILT_IN (olddecl))
+ /* Function declarations can either be 'static' or 'extern' (no
+ qualifier is equivalent to 'extern' - C99 6.2.2p5) and therefore
+ can never conflict with each other on account of linkage (6.2.2p4).
+ Multiple definitions are not allowed (6.9p3,5) but GCC permits
+ two definitions if one is 'extern inline' and one is not. The non-
+ extern-inline definition supersedes the extern-inline definition. */
+ else if (TREE_CODE (newdecl) == FUNCTION_DECL)
{
- /* A function declaration for a built-in function. */
- if (!TREE_PUBLIC (newdecl))
+ if (DECL_BUILT_IN (olddecl) && !TREE_PUBLIC (newdecl))
{
/* If you declare a built-in function name as static, the
built-in definition is overridden,
@@ -917,458 +1020,355 @@ duplicate_decls (tree newdecl, tree oldd
if (warn_shadow)
warning ("%Jshadowing built-in function '%D'", newdecl, newdecl);
/* Discard the old built-in function. */
- return 0;
+ return false;
}
- if (!types_match)
+
+ if (DECL_INITIAL (newdecl))
{
- /* Accept harmless mismatch in function types.
- This is for the ffs and fprintf builtins. */
- tree trytype = match_builtin_function_types (oldtype, newtype);
-
- if (trytype)
+ if (DECL_INITIAL (olddecl)
+ && !(DECL_DECLARED_INLINE_P (olddecl)
+ && DECL_EXTERNAL (olddecl)
+ && !(DECL_DECLARED_INLINE_P (newdecl)
+ && DECL_EXTERNAL (newdecl))))
{
- types_match = comptypes (newtype, trytype, COMPARE_STRICT);
- if (types_match)
- oldtype = trytype;
- if (! different_binding_level)
- TREE_TYPE (olddecl) = oldtype;
+ error ("%Jredefinition of '%D'", newdecl, newdecl);
+ locate_old_decl (olddecl, error);
+ return false;
+ }
+ }
+ /* If we have a prototype after an old-style function definition,
+ the argument types must be checked specially. */
+ else if (DECL_INITIAL (olddecl)
+ && !TYPE_ARG_TYPES (oldtype) && TYPE_ARG_TYPES (newtype)
+ && TYPE_ACTUAL_ARG_TYPES (oldtype)
+ && !validate_proto_after_old_defn (newdecl, newtype, oldtype))
+ {
+ locate_old_decl (olddecl, error);
+ return false;
+ }
+ /* Mismatched non-static and static is considered poor style.
+ We only diagnose static then non-static if -Wtraditional,
+ because it is the most convenient way to get some effects
+ (see e.g. what unwind-dw2-fde-glibc.c does to the definition
+ of _Unwind_Find_FDE in unwind-dw2-fde.c). Revisit? */
+ if (TREE_PUBLIC (olddecl) && !TREE_PUBLIC (newdecl))
+ {
+ /* A static function declaration for a predeclared function
+ that isn't actually built in, silently overrides the
+ default. Objective C uses these. See also above.
+ FIXME: Make Objective C use normal builtins. */
+ if (TREE_CODE (olddecl) == FUNCTION_DECL
+ && DECL_SOURCE_LINE (olddecl) == 0)
+ return false;
+ else
+ {
+ warning ("%Jstatic declaration of '%D' follows "
+ "non-static declaration", newdecl, newdecl);
+ warned = true;
}
}
- if (!types_match)
+ else if (TREE_PUBLIC (newdecl) && !TREE_PUBLIC (olddecl)
+ && warn_traditional)
{
- /* If types don't match for a built-in, throw away the built-in. */
- warning ("%Jconflicting types for built-in function '%D'",
- newdecl, newdecl);
- return 0;
+ warning ("%Jnon-static declaration of '%D' follows "
+ "static declaration", newdecl, newdecl);
+ warned = true;
}
}
- else if (TREE_CODE (olddecl) == FUNCTION_DECL
- && DECL_SOURCE_LINE (olddecl) == 0)
+ else if (TREE_CODE (newdecl) == VAR_DECL)
{
- /* A function declaration for a predeclared function
- that isn't actually built in. */
- if (!TREE_PUBLIC (newdecl))
+ /* Only variables can be thread-local, and all declarations must
+ agree on this property. */
+ if (DECL_THREAD_LOCAL (newdecl) != DECL_THREAD_LOCAL (olddecl))
{
- /* If you declare it as static, the
- default definition is overridden. */
- return 0;
+ if (DECL_THREAD_LOCAL (newdecl))
+ error ("%Jthread-local declaration of '%D' follows "
+ "non-thread-local declaration", newdecl, newdecl);
+ else
+ error ("%Jnon-thread-local declaration of '%D' follows "
+ "thread-local declaration", newdecl, newdecl);
+
+ locate_old_decl (olddecl, error);
+ return false;
}
- else if (!types_match)
+
+ /* Multiple initialized definitions are not allowed (6.9p3,5). */
+ if (DECL_INITIAL (newdecl) && DECL_INITIAL (olddecl))
{
- /* If the types don't match, preserve volatility indication.
- Later on, we will discard everything else about the
- default declaration. */
- TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
+ error ("%Jredefinition of '%D'", newdecl, newdecl);
+ locate_old_decl (olddecl, error);
+ return false;
}
- }
- /* Permit char *foo () to match void *foo (...) if not pedantic,
- if one of them came from a system header file. */
- else if (!types_match
- && TREE_CODE (olddecl) == FUNCTION_DECL
- && TREE_CODE (newdecl) == FUNCTION_DECL
- && TREE_CODE (TREE_TYPE (oldtype)) == POINTER_TYPE
- && TREE_CODE (TREE_TYPE (newtype)) == POINTER_TYPE
- && (DECL_IN_SYSTEM_HEADER (olddecl)
- || DECL_IN_SYSTEM_HEADER (newdecl))
- && ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (newtype))) == void_type_node
- && TYPE_ARG_TYPES (oldtype) == 0
- && self_promoting_args_p (TYPE_ARG_TYPES (newtype))
- && TREE_TYPE (TREE_TYPE (oldtype)) == char_type_node)
- ||
- (TREE_TYPE (TREE_TYPE (newtype)) == char_type_node
- && TYPE_ARG_TYPES (newtype) == 0
- && self_promoting_args_p (TYPE_ARG_TYPES (oldtype))
- && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (oldtype))) == void_type_node)))
- {
- if (pedantic)
- pedwarn ("%Jconflicting types for '%D'", newdecl, newdecl);
- /* Make sure we keep void * as ret type, not char *. */
- if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (oldtype))) == void_type_node)
- TREE_TYPE (newdecl) = newtype = oldtype;
-
- /* Set DECL_IN_SYSTEM_HEADER, so that if we see another declaration
- we will come back here again. */
- DECL_IN_SYSTEM_HEADER (newdecl) = 1;
- }
- /* Permit void foo (...) to match int foo (...) if the latter is the
- definition and implicit int was used. See c-torture/compile/920625-2.c. */
- else if (!types_match && new_is_definition
- && TREE_CODE (olddecl) == FUNCTION_DECL
- && TREE_CODE (newdecl) == FUNCTION_DECL
- && TYPE_MAIN_VARIANT (TREE_TYPE (oldtype)) == void_type_node
- && TYPE_MAIN_VARIANT (TREE_TYPE (newtype)) == integer_type_node
- && C_FUNCTION_IMPLICIT_INT (newdecl))
- {
- pedwarn ("%Jconflicting types for '%D'", newdecl, newdecl);
- /* Make sure we keep void as the return type. */
- TREE_TYPE (newdecl) = newtype = oldtype;
- C_FUNCTION_IMPLICIT_INT (newdecl) = 0;
- }
- else if (!types_match
- /* Permit char *foo (int, ...); followed by char *foo ();
- if not pedantic. */
- && ! (TREE_CODE (olddecl) == FUNCTION_DECL
- && ! pedantic
- /* Return types must still match. */
- && comptypes (TREE_TYPE (oldtype),
- TREE_TYPE (newtype), COMPARE_STRICT)
- && TYPE_ARG_TYPES (newtype) == 0))
- {
- error ("%Jconflicting types for '%D'", newdecl, newdecl);
- /* Check for function type mismatch
- involving an empty arglist vs a nonempty one. */
- if (TREE_CODE (olddecl) == FUNCTION_DECL
- && comptypes (TREE_TYPE (oldtype),
- TREE_TYPE (newtype), COMPARE_STRICT)
- && ((TYPE_ARG_TYPES (oldtype) == 0
- && DECL_INITIAL (olddecl) == 0)
- ||
- (TYPE_ARG_TYPES (newtype) == 0
- && DECL_INITIAL (newdecl) == 0)))
- {
- /* Classify the problem further. */
- tree t = TYPE_ARG_TYPES (oldtype);
- if (t == 0)
- t = TYPE_ARG_TYPES (newtype);
- for (; t; t = TREE_CHAIN (t))
- {
- tree type = TREE_VALUE (t);
- if (TREE_CHAIN (t) == 0
- && TYPE_MAIN_VARIANT (type) != void_type_node)
- {
- error ("a parameter list with an ellipsis can't match an empty parameter name list declaration");
- break;
- }
+ /* Objects declared at file scope: if at least one is 'extern',
+ it's fine (6.2.2p4); otherwise the linkage must agree (6.2.2p7). */
+ if (DECL_FILE_SCOPE_P (newdecl))
+ {
+ if (!DECL_EXTERNAL (newdecl)
+ && !DECL_EXTERNAL (olddecl)
+ && TREE_PUBLIC (newdecl) != TREE_PUBLIC (olddecl))
+ {
+ if (TREE_PUBLIC (newdecl))
+ error ("%Jnon-static declaration of '%D' follows "
+ "static declaration", newdecl, newdecl);
+ else
+ error ("%Jstatic declaration of '%D' follows "
+ "non-static declaration", newdecl, newdecl);
- if (c_type_promotes_to (type) != type)
- {
- error ("an argument type that has a default promotion can't match an empty parameter name list declaration");
- break;
- }
+ locate_old_decl (olddecl, error);
+ return false;
}
}
- if (C_DECL_IMPLICIT (olddecl))
- error ("%Jprevious implicit declaration of '%D'", olddecl, olddecl);
- else
- error ("%Jprevious declaration of '%D'", olddecl, olddecl);
+ /* Two objects with the same name declared at the same block
+ scope must both be external references (6.7p3). */
+ else if (DECL_CONTEXT (newdecl) == DECL_CONTEXT (olddecl)
+ && (!DECL_EXTERNAL (newdecl) || !DECL_EXTERNAL (olddecl)))
+ {
+ if (DECL_EXTERNAL (newdecl))
+ error ("%Jextern declaration of '%D' follows "
+ "declaration with no linkage", newdecl, newdecl);
+ else if (DECL_EXTERNAL (olddecl))
+ error ("%Jdeclaration of '%D' with no linkage follows "
+ "extern declaration", newdecl, newdecl);
+ else
+ error ("%Jredeclaration of '%D' with no linkage",
+ newdecl, newdecl);
- /* This is safer because the initializer might contain references
- to variables that were declared between olddecl and newdecl. This
- will make the initializer invalid for olddecl in case it gets
- assigned to olddecl below. */
- if (TREE_CODE (newdecl) == VAR_DECL)
- DECL_INITIAL (newdecl) = 0;
+ locate_old_decl (olddecl, error);
+ return false;
+ }
}
- /* TLS cannot follow non-TLS declaration. */
- else if (TREE_CODE (olddecl) == VAR_DECL && TREE_CODE (newdecl) == VAR_DECL
- && !DECL_THREAD_LOCAL (olddecl) && DECL_THREAD_LOCAL (newdecl))
- {
- error ("%Jthread-local declaration of '%D' follows non thread-local "
- "declaration", newdecl, newdecl);
- error ("%Jprevious declaration of '%D'", olddecl, olddecl);
- }
- /* non-TLS declaration cannot follow TLS declaration. */
- else if (TREE_CODE (olddecl) == VAR_DECL && TREE_CODE (newdecl) == VAR_DECL
- && DECL_THREAD_LOCAL (olddecl) && !DECL_THREAD_LOCAL (newdecl))
- {
- error ("%Jnon thread-local declaration of '%D' follows "
- "thread-local declaration", newdecl, newdecl);
- error ("%Jprevious declaration of '%D'", olddecl, olddecl);
+
+ /* warnings */
+ /* All decls must agree on a non-default visibility. */
+ if (DECL_VISIBILITY (newdecl) != VISIBILITY_DEFAULT
+ && DECL_VISIBILITY (olddecl) != VISIBILITY_DEFAULT
+ && DECL_VISIBILITY (newdecl) != DECL_VISIBILITY (olddecl))
+ {
+ warning ("%Jredeclaration of '%D' with different visibility "
+ "(old visibility preserved)", newdecl, newdecl);
+ warned = true;
}
- else
+
+ if (TREE_CODE (newdecl) == FUNCTION_DECL)
{
- errmsg = redeclaration_error_message (newdecl, olddecl);
- if (errmsg)
+ /* Diagnose inline __attribute__ ((noinline)) which is silly. */
+ if (DECL_DECLARED_INLINE_P (newdecl)
+ && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
{
- switch (errmsg)
- {
- case 1:
- error ("%Jredefinition of '%D'", newdecl, newdecl);
- break;
- case 2:
- error ("%Jredeclaration of '%D'", newdecl, newdecl);
- break;
- case 3:
- error ("%Jconflicting declarations of '%D'", newdecl, newdecl);
- break;
- default:
- abort ();
- }
-
- if (DECL_INITIAL (olddecl)
- && current_scope == global_scope)
- error ("%J'%D' previously defined here", olddecl, olddecl);
- else
- error ("%J'%D' previously declared here", olddecl, olddecl);
- return 0;
- }
- else if (TREE_CODE (newdecl) == TYPE_DECL
- && (DECL_IN_SYSTEM_HEADER (olddecl)
- || DECL_IN_SYSTEM_HEADER (newdecl)))
- {
- warning ("%Jredefinition of '%D'", newdecl, newdecl);
- if (DECL_INITIAL (olddecl) && current_scope == global_scope)
- warning ("%J'%D' previously defined here", olddecl, olddecl);
- else
- warning ("%J'%D' previously declared here", olddecl, olddecl);
+ warning ("%Jinline declaration of '%D' follows "
+ "declaration with attribute noinline", newdecl, newdecl);
+ warned = true;
}
- else if (TREE_CODE (olddecl) == FUNCTION_DECL
- && DECL_INITIAL (olddecl) != 0
- && TYPE_ARG_TYPES (oldtype) == 0
- && TYPE_ARG_TYPES (newtype) != 0
- && TYPE_ACTUAL_ARG_TYPES (oldtype) != 0)
- {
- tree type, parm;
- int nargs;
- /* Prototype decl follows defn w/o prototype. */
-
- for (parm = TYPE_ACTUAL_ARG_TYPES (oldtype),
- type = TYPE_ARG_TYPES (newtype),
- nargs = 1;
- ;
- parm = TREE_CHAIN (parm), type = TREE_CHAIN (type), nargs++)
- {
- if (TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == void_type_node
- && TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
- {
- warning ("%Jprototype for '%D' follows", newdecl, newdecl);
- warning ("%Jnon-prototype definition here", olddecl);
- break;
- }
- if (TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == void_type_node
- || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
- {
- error ("%Jprototype for '%D' follows and number of "
- "arguments doesn't match", newdecl, newdecl);
- error ("%Jnon-prototype definition here", olddecl);
- errmsg = 1;
- break;
- }
- /* Type for passing arg must be consistent
- with that declared for the arg. */
- if (! comptypes (TREE_VALUE (parm), TREE_VALUE (type),
- COMPARE_STRICT))
- {
- error ("%Jprototype for '%D' follows and argument %d "
- "doesn't match", newdecl, newdecl, nargs);
- error ("%Jnon-prototype definition here", olddecl);
- errmsg = 1;
- break;
- }
- }
- }
- /* Warn about mismatches in various flags. */
- else
+ else if (DECL_DECLARED_INLINE_P (olddecl)
+ && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
{
- /* Warn if function is now inline
- but was previously declared not inline and has been called. */
- if (TREE_CODE (olddecl) == FUNCTION_DECL
- && ! DECL_DECLARED_INLINE_P (olddecl)
- && DECL_DECLARED_INLINE_P (newdecl)
- && TREE_USED (olddecl))
- warning ("%J'%D' declared inline after being called",
- newdecl, newdecl);
- if (TREE_CODE (olddecl) == FUNCTION_DECL
- && ! DECL_DECLARED_INLINE_P (olddecl)
- && DECL_DECLARED_INLINE_P (newdecl)
- && DECL_INITIAL (olddecl) != 0)
- warning ("%J'%D' declared inline after its definition",
- newdecl, newdecl);
-
- /* If pedantic, warn when static declaration follows a non-static
- declaration. Otherwise, do so only for functions. */
- if ((pedantic || TREE_CODE (olddecl) == FUNCTION_DECL)
- && TREE_PUBLIC (olddecl)
- && !TREE_PUBLIC (newdecl))
- warning ("%Jstatic declaration for '%D' follows non-static",
- newdecl, newdecl);
-
- /* If warn_traditional, warn when a non-static function
- declaration follows a static one. */
- if (warn_traditional && !in_system_header
- && TREE_CODE (olddecl) == FUNCTION_DECL
- && !TREE_PUBLIC (olddecl)
- && TREE_PUBLIC (newdecl))
- warning ("%Jnon-static declaration for '%D' follows static",
- newdecl, newdecl);
-
- /* Warn when const declaration follows a non-const
- declaration, but not for functions. */
- if (TREE_CODE (olddecl) != FUNCTION_DECL
- && !TREE_READONLY (olddecl)
- && TREE_READONLY (newdecl))
- warning ("%Jconst declaration for '%D' follows non-const",
- newdecl, newdecl);
- /* These bits are logically part of the type, for variables.
- But not for functions
- (where qualifiers are not valid ANSI anyway). */
- else if (pedantic && TREE_CODE (olddecl) != FUNCTION_DECL
- && (TREE_READONLY (newdecl) != TREE_READONLY (olddecl)
- || TREE_THIS_VOLATILE (newdecl) != TREE_THIS_VOLATILE (olddecl)))
- pedwarn ("%Jtype qualifiers for '%D' conflict with previous "
- "declaration", newdecl, newdecl);
- }
- }
-
- /* Optionally warn about more than one declaration for the same name. */
- if (errmsg == 0 && warn_redundant_decls && DECL_SOURCE_LINE (olddecl) != 0
- /* Don't warn about a function declaration
- followed by a definition. */
- && !(TREE_CODE (newdecl) == FUNCTION_DECL && DECL_INITIAL (newdecl) != 0
- && DECL_INITIAL (olddecl) == 0)
- /* Don't warn about extern decl followed by (tentative) definition. */
- && !(DECL_EXTERNAL (olddecl) && ! DECL_EXTERNAL (newdecl)))
- {
- warning ("%Jredundant redeclaration of '%D' in same scope",
- newdecl, newdecl);
- warning ("%Jprevious declaration of '%D'", olddecl, olddecl);
- }
-
- /* Copy all the DECL_... slots specified in the new decl
- except for any that we copy here from the old type.
-
- Past this point, we don't change OLDTYPE and NEWTYPE
- even if we change the types of NEWDECL and OLDDECL. */
-
- if (types_match)
- {
- /* When copying info to olddecl, we store into write_olddecl
- instead. This allows us to avoid modifying olddecl when
- different_binding_level is true. */
- tree write_olddecl = different_binding_level ? newdecl : olddecl;
+ warning ("%Jdeclaration of '%D' with attribute noinline follows "
+ "inline declaration ", newdecl, newdecl);
+ warned = true;
+ }
- /* Merge the data types specified in the two decls. */
- if (TREE_CODE (newdecl) != FUNCTION_DECL || !DECL_BUILT_IN (olddecl))
+ /* Inline declaration after use or definition.
+ ??? Should we still warn about this now we have unit-at-a-time
+ mode and can get it right? */
+ if (DECL_DECLARED_INLINE_P (newdecl) && !DECL_DECLARED_INLINE_P (olddecl))
{
- if (different_binding_level)
+ if (TREE_USED (olddecl))
{
- if (TYPE_ARG_TYPES (oldtype) != 0
- && TYPE_ARG_TYPES (newtype) == 0)
- TREE_TYPE (newdecl) = common_type (newtype, oldtype);
- else
- TREE_TYPE (newdecl)
- = build_type_attribute_variant
- (newtype,
- merge_attributes (TYPE_ATTRIBUTES (newtype),
- TYPE_ATTRIBUTES (oldtype)));
+ warning ("%J'%D' declared inline after being called");
+ warned = true;
+ }
+ else if (DECL_INITIAL (olddecl))
+ {
+ warning ("%J'%D' declared inline after its definition");
+ warned = true;
}
+ }
+ }
+ else /* VAR_DECL */
+ {
+ /* These bits are only type qualifiers when applied to objects. */
+ if (TREE_THIS_VOLATILE (newdecl) != TREE_THIS_VOLATILE (olddecl))
+ {
+ if (TREE_THIS_VOLATILE (newdecl))
+ pedwarn ("%Jvolatile declaration of '%D' follows "
+ "non-volatile declaration", newdecl, newdecl);
else
- TREE_TYPE (newdecl)
- = TREE_TYPE (olddecl)
- = common_type (newtype, oldtype);
+ pedwarn ("%Jnon-volatile declaration of '%D' follows "
+ "volatile declaration", newdecl, newdecl);
+ pedwarned = true;
+ }
+ if (TREE_READONLY (newdecl) != TREE_READONLY (olddecl))
+ {
+ if (TREE_READONLY (newdecl))
+ pedwarn ("%Jconst declaration of '%D' follows "
+ "non-const declaration", newdecl, newdecl);
+ else
+ pedwarn ("%Jnon-const declaration of '%D' follows "
+ "const declaration", newdecl, newdecl);
+ pedwarned = true;
}
+ }
+
+ /* Optional warning for completely redundant decls. */
+ if (!warned && !pedwarned
+ && warn_redundant_decls
+ /* Don't warn about a function declaration followed by a
+ definition. */
+ && !(TREE_CODE (newdecl) == FUNCTION_DECL
+ && DECL_INITIAL (newdecl) && !DECL_INITIAL (olddecl))
+ /* Don't warn about an extern followed by a definition. */
+ && !(DECL_EXTERNAL (olddecl) && !DECL_EXTERNAL (newdecl)))
+ {
+ warning ("%Jredundant redeclaration of '%D'", newdecl, newdecl);
+ warned = true;
+ }
+
+ /* Report location of previous decl/defn in a consistent manner. */
+ if (warned || pedwarned)
+ locate_old_decl (olddecl, pedwarned ? pedwarn : warning);
+
+ *newtypep = newtype;
+ *oldtypep = oldtype;
+ return true;
+}
+
+/* Subroutine of duplicate_decls. NEWDECL has been found to be
+ consistent with OLDDECL, but carries new information. Merge the
+ new information into OLDDECL. If DIFFERENT_BINDING_LEVEL or
+ DIFFERENT_TU is true, avoid completely merging the decls, as this
+ will break assumptions elsewhere. This function issues no
+ diagnostics. */
+
+static void
+merge_decls (tree newdecl, tree olddecl, tree newtype, tree oldtype,
+ bool different_binding_level, bool different_tu)
+{
+ int new_is_definition = (TREE_CODE (newdecl) == FUNCTION_DECL
+ && DECL_INITIAL (newdecl) != 0);
+
+ /* When copying info to olddecl, we store into write_olddecl
+ instead. This allows us to avoid modifying olddecl when
+ different_binding_level is true. */
+ tree write_olddecl = different_binding_level ? newdecl : olddecl;
+
+ /* For real parm decl following a forward decl, return 1 so old decl
+ will be reused. Only allow this to happen once. */
+ if (TREE_CODE (newdecl) == PARM_DECL
+ && TREE_ASM_WRITTEN (olddecl) && ! TREE_ASM_WRITTEN (newdecl))
+ {
+ TREE_ASM_WRITTEN (olddecl) = 0;
+ return;
+ }
+
+ DECL_ATTRIBUTES (newdecl)
+ = (*targetm.merge_decl_attributes) (olddecl, newdecl);
- /* Lay the type out, unless already done. */
- if (oldtype != TREE_TYPE (newdecl))
+ /* Merge the data types specified in the two decls. */
+ if (TREE_CODE (newdecl) != FUNCTION_DECL || !DECL_BUILT_IN (olddecl))
+ {
+ if (different_binding_level)
{
- if (TREE_TYPE (newdecl) != error_mark_node)
- layout_type (TREE_TYPE (newdecl));
- if (TREE_CODE (newdecl) != FUNCTION_DECL
- && TREE_CODE (newdecl) != TYPE_DECL
- && TREE_CODE (newdecl) != CONST_DECL)
- layout_decl (newdecl, 0);
+ if (TYPE_ARG_TYPES (oldtype) != 0
+ && TYPE_ARG_TYPES (newtype) == 0)
+ TREE_TYPE (newdecl) = common_type (newtype, oldtype);
+ else
+ TREE_TYPE (newdecl)
+ = build_type_attribute_variant
+ (newtype,
+ merge_attributes (TYPE_ATTRIBUTES (newtype),
+ TYPE_ATTRIBUTES (oldtype)));
}
else
- {
- /* Since the type is OLDDECL's, make OLDDECL's size go with. */
- DECL_SIZE (newdecl) = DECL_SIZE (olddecl);
- DECL_SIZE_UNIT (newdecl) = DECL_SIZE_UNIT (olddecl);
- DECL_MODE (newdecl) = DECL_MODE (olddecl);
- if (TREE_CODE (olddecl) != FUNCTION_DECL)
- if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
- {
- DECL_ALIGN (newdecl) = DECL_ALIGN (olddecl);
- DECL_USER_ALIGN (newdecl) |= DECL_ALIGN (olddecl);
- }
- }
-
- /* Keep the old rtl since we can safely use it. */
- COPY_DECL_RTL (olddecl, newdecl);
-
- /* Merge the type qualifiers. */
- if (TREE_READONLY (newdecl))
- TREE_READONLY (write_olddecl) = 1;
-
- if (TREE_THIS_VOLATILE (newdecl))
- {
- TREE_THIS_VOLATILE (write_olddecl) = 1;
- if (TREE_CODE (newdecl) == VAR_DECL
- /* If an automatic variable is re-declared in the same
- function scope, but the old declaration was not
- volatile, make_var_volatile() would crash because the
- variable would have been assigned to a pseudo, not a
- MEM. Since this duplicate declaration is invalid
- anyway, we just skip the call. */
- && errmsg == 0)
- make_var_volatile (newdecl);
- }
-
- /* Keep source location of definition rather than declaration. */
- /* When called with different_binding_level set, keep the old
- information so that meaningful diagnostics can be given. */
- if (DECL_INITIAL (newdecl) == 0 && DECL_INITIAL (olddecl) != 0
- && ! different_binding_level)
- DECL_SOURCE_LOCATION (newdecl) = DECL_SOURCE_LOCATION (olddecl);
-
- /* Merge the unused-warning information. */
- if (DECL_IN_SYSTEM_HEADER (olddecl))
- DECL_IN_SYSTEM_HEADER (newdecl) = 1;
- else if (DECL_IN_SYSTEM_HEADER (newdecl))
- DECL_IN_SYSTEM_HEADER (write_olddecl) = 1;
-
- /* Merge the initialization information. */
- /* When called with different_binding_level set, don't copy over
- DECL_INITIAL, so that we don't accidentally change function
- declarations into function definitions. */
- if (DECL_INITIAL (newdecl) == 0 && ! different_binding_level)
- DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
-
- /* Merge the section attribute.
- We want to issue an error if the sections conflict but that must be
- done later in decl_attributes since we are called before attributes
- are assigned. */
- if (DECL_SECTION_NAME (newdecl) == NULL_TREE)
- DECL_SECTION_NAME (newdecl) = DECL_SECTION_NAME (olddecl);
-
- /* Copy the assembler name.
- Currently, it can only be defined in the prototype. */
- COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);
+ TREE_TYPE (newdecl)
+ = TREE_TYPE (olddecl)
+ = common_type (newtype, oldtype);
+ }
- /* If either declaration has a nondefault visibility, use it. */
- if (DECL_VISIBILITY (olddecl) != VISIBILITY_DEFAULT)
- {
- if (DECL_VISIBILITY (newdecl) != VISIBILITY_DEFAULT
- && DECL_VISIBILITY (newdecl) != DECL_VISIBILITY (olddecl))
- {
- warning ("%J'%D': visibility attribute ignored because it",
- newdecl, newdecl);
- warning ("%Jconflicts with previous declaration here", olddecl);
- }
- DECL_VISIBILITY (newdecl) = DECL_VISIBILITY (olddecl);
- }
+ /* Lay the type out, unless already done. */
+ if (oldtype != TREE_TYPE (newdecl))
+ {
+ if (TREE_TYPE (newdecl) != error_mark_node)
+ layout_type (TREE_TYPE (newdecl));
+ if (TREE_CODE (newdecl) != FUNCTION_DECL
+ && TREE_CODE (newdecl) != TYPE_DECL
+ && TREE_CODE (newdecl) != CONST_DECL)
+ layout_decl (newdecl, 0);
+ }
+ else
+ {
+ /* Since the type is OLDDECL's, make OLDDECL's size go with. */
+ DECL_SIZE (newdecl) = DECL_SIZE (olddecl);
+ DECL_SIZE_UNIT (newdecl) = DECL_SIZE_UNIT (olddecl);
+ DECL_MODE (newdecl) = DECL_MODE (olddecl);
+ if (TREE_CODE (olddecl) != FUNCTION_DECL)
+ if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
+ {
+ DECL_ALIGN (newdecl) = DECL_ALIGN (olddecl);
+ DECL_USER_ALIGN (newdecl) |= DECL_ALIGN (olddecl);
+ }
+ }
+
+ /* Keep the old rtl since we can safely use it. */
+ COPY_DECL_RTL (olddecl, newdecl);
+
+ /* Merge the type qualifiers. */
+ if (TREE_READONLY (newdecl))
+ TREE_READONLY (write_olddecl) = 1;
- if (TREE_CODE (newdecl) == FUNCTION_DECL)
- {
- DECL_STATIC_CONSTRUCTOR(newdecl) |= DECL_STATIC_CONSTRUCTOR(olddecl);
- DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
- DECL_NO_LIMIT_STACK (newdecl) |= DECL_NO_LIMIT_STACK (olddecl);
- DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
- |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
- TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
- TREE_READONLY (newdecl) |= TREE_READONLY (olddecl);
- DECL_IS_MALLOC (newdecl) |= DECL_IS_MALLOC (olddecl);
- DECL_IS_PURE (newdecl) |= DECL_IS_PURE (olddecl);
- }
+ if (TREE_THIS_VOLATILE (newdecl))
+ {
+ TREE_THIS_VOLATILE (write_olddecl) = 1;
+ if (TREE_CODE (newdecl) == VAR_DECL)
+ make_var_volatile (newdecl);
}
- /* If cannot merge, then use the new type and qualifiers,
- and don't preserve the old rtl. */
- else if (! different_binding_level)
- {
- TREE_TYPE (olddecl) = TREE_TYPE (newdecl);
- TREE_READONLY (olddecl) = TREE_READONLY (newdecl);
- TREE_THIS_VOLATILE (olddecl) = TREE_THIS_VOLATILE (newdecl);
- TREE_SIDE_EFFECTS (olddecl) = TREE_SIDE_EFFECTS (newdecl);
+
+ /* Keep source location of definition rather than declaration. */
+ /* When called with different_binding_level set, keep the old
+ information so that meaningful diagnostics can be given. */
+ if (DECL_INITIAL (newdecl) == 0 && DECL_INITIAL (olddecl) != 0
+ && ! different_binding_level)
+ DECL_SOURCE_LOCATION (newdecl) = DECL_SOURCE_LOCATION (olddecl);
+
+ /* Merge the unused-warning information. */
+ if (DECL_IN_SYSTEM_HEADER (olddecl))
+ DECL_IN_SYSTEM_HEADER (newdecl) = 1;
+ else if (DECL_IN_SYSTEM_HEADER (newdecl))
+ DECL_IN_SYSTEM_HEADER (write_olddecl) = 1;
+
+ /* Merge the initialization information. */
+ /* When called with different_binding_level set, don't copy over
+ DECL_INITIAL, so that we don't accidentally change function
+ declarations into function definitions. */
+ if (DECL_INITIAL (newdecl) == 0 && ! different_binding_level)
+ DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
+
+ /* Merge the section attribute.
+ We want to issue an error if the sections conflict but that must be
+ done later in decl_attributes since we are called before attributes
+ are assigned. */
+ if (DECL_SECTION_NAME (newdecl) == NULL_TREE)
+ DECL_SECTION_NAME (newdecl) = DECL_SECTION_NAME (olddecl);
+
+ /* Copy the assembler name.
+ Currently, it can only be defined in the prototype. */
+ COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);
+
+ /* If either declaration has a nondefault visibility, use it. */
+ if (DECL_VISIBILITY (olddecl) != VISIBILITY_DEFAULT)
+ DECL_VISIBILITY (newdecl) = DECL_VISIBILITY (olddecl);
+
+ if (TREE_CODE (newdecl) == FUNCTION_DECL)
+ {
+ DECL_STATIC_CONSTRUCTOR(newdecl) |= DECL_STATIC_CONSTRUCTOR(olddecl);
+ DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
+ DECL_NO_LIMIT_STACK (newdecl) |= DECL_NO_LIMIT_STACK (olddecl);
+ DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
+ |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
+ TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
+ TREE_READONLY (newdecl) |= TREE_READONLY (olddecl);
+ DECL_IS_MALLOC (newdecl) |= DECL_IS_MALLOC (olddecl);
+ DECL_IS_PURE (newdecl) |= DECL_IS_PURE (olddecl);
}
/* Merge the storage class information. */
@@ -1448,9 +1448,9 @@ duplicate_decls (tree newdecl, tree oldd
if (DECL_BUILT_IN (olddecl))
{
- /* Get rid of any built-in function if new arg types don't match it
- or if we have a function definition. */
- if (! types_match || new_is_definition)
+ /* Get rid of any built-in function if we have a function
+ definition. */
+ if (new_is_definition)
{
if (! different_binding_level)
{
@@ -1502,7 +1502,7 @@ duplicate_decls (tree newdecl, tree oldd
}
}
if (different_binding_level)
- return 0;
+ return;
/* Copy most of the decl-specific fields of NEWDECL into OLDDECL.
But preserve OLDDECL's DECL_UID. */
@@ -1515,10 +1515,6 @@ duplicate_decls (tree newdecl, tree oldd
DECL_UID (olddecl) = olddecl_uid;
}
- /* NEWDECL contains the merged attribute lists.
- Update OLDDECL to be the same. */
- DECL_ATTRIBUTES (olddecl) = DECL_ATTRIBUTES (newdecl);
-
/* If OLDDECL had its DECL_RTL instantiated, re-invoke make_decl_rtl
so that encode_section_info has a chance to look at the new decl
flags and attributes. */
@@ -1527,10 +1523,34 @@ duplicate_decls (tree newdecl, tree oldd
|| (TREE_CODE (olddecl) == VAR_DECL
&& TREE_STATIC (olddecl))))
make_decl_rtl (olddecl, NULL);
-
- return 1;
}
+/* Handle when a new declaration NEWDECL has the same name as an old
+ one OLDDECL in the same binding contour. Prints an error message
+ if appropriate.
+
+ If safely possible, alter OLDDECL to look like NEWDECL, and return
+ true. Otherwise, return false.
+
+ When DIFFERENT_BINDING_LEVEL is true, NEWDECL is an external
+ declaration, and OLDDECL is in an outer scope and should thus not
+ be changed. */
+
+static bool
+duplicate_decls (tree newdecl, tree olddecl,
+ bool different_binding_level, bool different_tu)
+{
+ tree newtype, oldtype;
+
+ if (!diagnose_mismatched_decls (newdecl, olddecl, &newtype, &oldtype))
+ return false;
+
+ merge_decls (newdecl, olddecl, newtype, oldtype,
+ different_binding_level, different_tu);
+ return !different_binding_level;
+}
+
+
/* Return any external DECL associated with ID, whether or not it is
currently in scope. */
@@ -1888,69 +1908,6 @@ implicit_decl_warning (tree id)
error ("implicit declaration of function `%s'", name);
else if (mesg_implicit_function_declaration == 1)
warning ("implicit declaration of function `%s'", name);
-}
-
-/* Return zero if the declaration NEWDECL is valid
- when the declaration OLDDECL (assumed to be for the same name)
- has already been seen.
- Otherwise return 1 if NEWDECL is a redefinition, 2 if it is a redeclaration,
- and 3 if it is a conflicting declaration. */
-
-static int
-redeclaration_error_message (tree newdecl, tree olddecl)
-{
- if (TREE_CODE (newdecl) == TYPE_DECL)
- {
- /* Do not complain about type redeclarations where at least one
- declaration was in a system header. */
- if (DECL_IN_SYSTEM_HEADER (olddecl) || DECL_IN_SYSTEM_HEADER (newdecl))
- return 0;
- return 1;
- }
- else if (TREE_CODE (newdecl) == FUNCTION_DECL)
- {
- /* Declarations of functions can insist on internal linkage
- but they can't be inconsistent with internal linkage,
- so there can be no error on that account.
- However defining the same name twice is no good. */
- if (DECL_INITIAL (olddecl) != 0 && DECL_INITIAL (newdecl) != 0
- /* However, defining once as extern inline and a second
- time in another way is ok. */
- && ! (DECL_DECLARED_INLINE_P (olddecl) && DECL_EXTERNAL (olddecl)
- && ! (DECL_DECLARED_INLINE_P (newdecl)
- && DECL_EXTERNAL (newdecl))))
- return 1;
- return 0;
- }
- else if (DECL_FILE_SCOPE_P (newdecl))
- {
- /* Objects declared at file scope: */
- /* If at least one is a reference, it's ok. */
- if (DECL_EXTERNAL (newdecl) || DECL_EXTERNAL (olddecl))
- return 0;
- /* Reject two definitions. */
- if (DECL_INITIAL (olddecl) != 0 && DECL_INITIAL (newdecl) != 0)
- return 1;
- /* Now we have two tentative defs, or one tentative and one real def. */
- /* Insist that the linkage match. */
- if (TREE_PUBLIC (olddecl) != TREE_PUBLIC (newdecl))
- return 3;
- return 0;
- }
- else if (current_scope->parm_flag
- && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
- return 0;
- else
- {
- /* Newdecl has block scope. If olddecl has block scope also, then
- reject two definitions, and reject a definition together with an
- external reference. Otherwise, it is OK, because newdecl must
- be an extern reference to olddecl. */
- if (!(DECL_EXTERNAL (newdecl) && DECL_EXTERNAL (olddecl))
- && DECL_CONTEXT (newdecl) == DECL_CONTEXT (olddecl))
- return 2;
- return 0;
- }
}
/* Issue an error message for a reference to an undeclared variable
===================================================================
Index: testsuite/gcc.dg/Wshadow-1.c
--- testsuite/gcc.dg/Wshadow-1.c 11 Apr 2003 04:26:55 -0000 1.3
+++ testsuite/gcc.dg/Wshadow-1.c 11 Jan 2004 01:08:45 -0000
@@ -10,7 +10,7 @@ void foo (double decl1) /* { dg-warning
{
}
-void foo1 (int d) /* { dg-warning "previous declaration" } */
+void foo1 (int d) /* { dg-warning "previous definition" } */
{
double d; /* { dg-bogus "warning" "warning in place of error" } */
/* { dg-error "redeclared as different" "" { target *-*-* } 15 } */
===================================================================
Index: testsuite/gcc.dg/attr-noinline.c
--- testsuite/gcc.dg/attr-noinline.c 6 Feb 2002 20:40:17 -0000 1.2
+++ testsuite/gcc.dg/attr-noinline.c 11 Jan 2004 01:08:45 -0000
@@ -13,33 +13,33 @@ static inline void __attribute__((__noin
static void function_declaration_both_after(void) {}
-static void function_declaration_noinline_before(void) __attribute__((__noinline__)); /* { dg-warning "previous declaration \[^\n\]* with attribute noinline" "" } */
+static void function_declaration_noinline_before(void) __attribute__((__noinline__)); /* { dg-warning "previous declaration" "" } */
-static inline void function_declaration_noinline_before(void) {} /* { dg-warning "function \[^\n\]* redeclared as inline" "" } */
+static inline void function_declaration_noinline_before(void) {} /* { dg-warning "follows declaration with attribute noinline" "" } */
-static inline void function_declaration_noinline_after(void) {} /* { dg-warning "previous declaration \[^\n\]* was inline" "" } */
+static inline void function_declaration_noinline_after(void) {} /* { dg-warning "previous definition" "" } */
-static void function_declaration_noinline_after(void) __attribute__((__noinline__)); /* { dg-warning "function \[^\n\]* redeclared with attribute noinline" "" } */
+static void function_declaration_noinline_after(void) __attribute__((__noinline__)); /* { dg-warning "follows inline declaration" "" } */
-static inline void function_declaration_inline_before(void); /* { dg-warning "previous declaration \[^\n\]* was inline" "" } */
+static inline void function_declaration_inline_before(void); /* { dg-warning "previous declaration" "" } */
-static void __attribute__((__noinline__)) function_declaration_inline_before(void) {} /* { dg-warning "function \[^\n\]* redeclared with attribute noinline" "" } */
+static void __attribute__((__noinline__)) function_declaration_inline_before(void) {} /* { dg-warning "follows inline declaration" "" } */
-static inline void function_declaration_inline_noinline_before(void); /* { dg-warning "previous declaration \[^\n\]* was inline" "" } */
+static inline void function_declaration_inline_noinline_before(void); /* { dg-warning "previous declaration" "" } */
-static void function_declaration_inline_noinline_before(void) __attribute__((__noinline__)); /* { dg-warning "function \[^\n\]* redeclared with attribute noinline" "" } */
+static void function_declaration_inline_noinline_before(void) __attribute__((__noinline__)); /* { dg-warning "follows inline declaration" "" } */
static void function_declaration_inline_noinline_before(void) {}
static inline void function_declaration_inline_noinline_after(void);
-static void function_declaration_inline_noinline_after(void) {} /* { dg-warning "previous declaration \[^\n\]* was inline" "" } */
+static void function_declaration_inline_noinline_after(void) {} /* { dg-warning "previous definition" "" } */
-static void function_declaration_inline_noinline_after(void) __attribute__((__noinline__)); /* { dg-warning "function \[^\n\]* redeclared with attribute noinline" "" } */
+static void function_declaration_inline_noinline_after(void) __attribute__((__noinline__)); /* { dg-warning "follows inline declaration" "" } */
-static void function_declaration_noinline_inline_before(void) __attribute__((__noinline__)); /* { dg-warning "previous declaration\[^\n\]* with attribute noinline" "" } */
+static void function_declaration_noinline_inline_before(void) __attribute__((__noinline__)); /* { dg-warning "previous declaration" "" } */
-static inline void function_declaration_noinline_inline_before(void); /* { dg-warning "function \[^\n\]* redeclared as inline" "" } */
+static inline void function_declaration_noinline_inline_before(void); /* { dg-warning "follows declaration with attribute noinline" "" } */
static void function_declaration_noinline_inline_before(void) {}
===================================================================
Index: testsuite/gcc.dg/decl-3.c
--- testsuite/gcc.dg/decl-3.c 12 Mar 2003 09:54:38 -0000 1.1
+++ testsuite/gcc.dg/decl-3.c 11 Jan 2004 01:08:45 -0000
@@ -1,5 +1,5 @@
/* PR c/9928 */
/* { dg-do compile } */
-enum { CODES }; /* { dg-error "previous declaration" } */
+enum { CODES }; /* { dg-error "previous definition" } */
enum { CODES }; /* { dg-error "conflicting types" } */
===================================================================
Index: testsuite/gcc.dg/redecl-1.c
--- testsuite/gcc.dg/redecl-1.c 11 Apr 2003 04:26:55 -0000 1.1
+++ testsuite/gcc.dg/redecl-1.c 11 Jan 2004 01:08:45 -0000
@@ -74,7 +74,7 @@ void test5(void)
/* Extern then static, both at file scope. */
-extern int test6(int); /* { dg-warning "previous" "" { xfail *-*-* } } */
+extern int test6(int); /* { dg-warning "previous" "" } */
static int test6(int x)
{ return x; } /* { dg-warning "follows non-static" } */
@@ -83,7 +83,7 @@ static int test6(int x)
void prime7(void)
{
- extern int test7(int); /* { dg-warning "previous" "" { xfail *-*-* } } */
+ extern int test7(int); /* { dg-warning "previous" "" } */
}
static int test7(int x)
@@ -93,7 +93,7 @@ static int test7(int x)
void prime8(void)
{
- test8(); /* { dg-warning "previous" "" { xfail *-*-* } } */
+ test8(); /* { dg-warning "previous" "" } */
/* { dg-warning "implicit" "" { target *-*-* } 96 } */
}
===================================================================
Index: testsuite/gcc.dg/visibility-7.c
--- testsuite/gcc.dg/visibility-7.c 10 Dec 2003 06:34:45 -0000 1.1
+++ testsuite/gcc.dg/visibility-7.c 11 Jan 2004 01:08:45 -0000
@@ -5,8 +5,8 @@
extern int
__attribute__((visibility ("hidden")))
-xyzzy; /* { dg-warning "previous declaration here" "" } */
+xyzzy; /* { dg-warning "previous declaration" "" } */
int
__attribute__((visibility ("protected")))
-xyzzy = 5; /* { dg-warning "visibility attribute ignored" "" } */
+xyzzy = 5; /* { dg-warning "different visibility" "" } */
===================================================================
Index: testsuite/gcc.dg/wtr-static-1.c
--- testsuite/gcc.dg/wtr-static-1.c 3 Jul 2002 02:41:34 -0000 1.3
+++ testsuite/gcc.dg/wtr-static-1.c 11 Jan 2004 01:08:45 -0000
@@ -4,7 +4,7 @@
/* { dg-do compile } */
/* { dg-options "-Wtraditional" } */
-static void testfunc1(void);
+static void testfunc1(void); /* { dg-warning "previous declaration" } */
void testfunc1() {} /* { dg-warning "non-static.*follows static" "non-static follows static" } */
# 11 "sys-header.h" 3
===================================================================
Index: testsuite/gcc.dg/noncompile/20020213-1.c
--- testsuite/gcc.dg/noncompile/20020213-1.c 14 Feb 2002 10:22:53 -0000 1.1
+++ testsuite/gcc.dg/noncompile/20020213-1.c 11 Jan 2004 01:08:45 -0000
@@ -24,7 +24,6 @@ int main ()
return 0;
}
-/* { dg-warning "passing arg 2 of" "2nd incompatible" { target *-*-* } 15 } */
/* { dg-warning "passing arg 1 of" "1st incompatible" { target *-*-* } 16 } */
/* { dg-warning "passing arg 2 of" "2nd incompatible" { target *-*-* } 16 } */
/* { dg-warning "passing arg 1 of" "1st incompatible" { target *-*-* } 18 } */
===================================================================
Index: testsuite/gcc.dg/noncompile/20020220-1.c
--- testsuite/gcc.dg/noncompile/20020220-1.c 20 Feb 2002 22:59:35 -0000 1.1
+++ testsuite/gcc.dg/noncompile/20020220-1.c 11 Jan 2004 01:08:45 -0000
@@ -6,7 +6,7 @@ int foo (const char*, const char*);
void bar (void)
{
const char *s = "bar";
- int i; /* { dg-error "previously declared here" } */
+ int i; /* { dg-error "previous declaration" } */
int size = 2;
int i = foo (s, s + size); /* { dg-error "redeclaration of" } */
}
===================================================================
Index: testsuite/objc.dg/method-1.m
--- testsuite/objc.dg/method-1.m 25 Sep 2003 01:26:01 -0000 1.3
+++ testsuite/objc.dg/method-1.m 11 Jan 2004 01:08:45 -0000
@@ -16,9 +16,8 @@
@end
@implementation class3
-- (int) meth1 { return 0; }
+- (int) meth1 { return 0; } /* { dg-error "previous definition" } */
- (int) meth1 { return 0; } /* { dg-error "redefinition of" } */
-/* { dg-error "previously defined here" "" { target *-*-* } 19 } */
@end
@interface class4
@@ -26,7 +25,6 @@
@end
@implementation class4
-+ (void) meth1 {}
++ (void) meth1 {} /* { dg-error "previous definition" } */
+ (void) meth1 {} /* { dg-error "redefinition of" } */
-/* { dg-error "previously defined here" "" { target *-*-* } 29 } */
@end