This is actually a (was: Re:) Patch for better diagnostic
Manfred Hollstein
manfred@s-direktnet.de
Sat Mar 14 06:27:00 GMT 1998
Jason, how about the patch? In the meantime I `optimized' it a little
bit in order to terminate the two new for loops in
abstract_virtuals_error as soon as we know what to complain about,
instead of running until the list's end.
Sat Mar 14 15:23:23 1998 Manfred Hollstein <manfred@s-direktnet.de>
* cp-tree.h (struct lang_decl_flags): Add needs_final_overrider.
(DECL_NEEDS_FINAL_OVERRIDER_P): New macro.
* class.c (override_one_vtable): Set DECL_NEEDS_FINAL_OVERRIDER_P.
* decl.c (duplicate_decls): Propagate it.
* typeck2.c (abstract_virtuals_error): Use two loops to emit
abstract virtual functions and virtual functions which need a
final overrider separately.
diff -rup -x CVS -x *.o -x *.info* -x *.html* -x *.elc -x *.dvi -x *.orig -x *~ -x version.el egcs-980313.orig/gcc/cp/class.c egcs-980313/gcc/cp/class.c
--- egcs-980313.orig/gcc/cp/class.c Thu Mar 5 09:20:44 1998
+++ egcs-980313/gcc/cp/class.c Sat Mar 14 15:18:57 1998
@@ -2725,6 +2725,7 @@ override_one_vtable (binfo, old, t)
fndecl = copy_node (fndecl);
copy_lang_decl (fndecl);
DECL_ABSTRACT_VIRTUAL_P (fndecl) = 1;
+ DECL_NEEDS_FINAL_OVERRIDER_P (fndecl) = 1;
/* Make sure we search for it later. */
if (! CLASSTYPE_ABSTRACT_VIRTUALS (t))
CLASSTYPE_ABSTRACT_VIRTUALS (t) = error_mark_node;
diff -rup -x CVS -x *.o -x *.info* -x *.html* -x *.elc -x *.dvi -x *.orig -x *~ -x version.el egcs-980313.orig/gcc/cp/cp-tree.h egcs-980313/gcc/cp/cp-tree.h
--- egcs-980313.orig/gcc/cp/cp-tree.h Thu Mar 5 09:20:44 1998
+++ egcs-980313/gcc/cp/cp-tree.h Sat Mar 14 15:18:57 1998
@@ -969,7 +969,8 @@ struct lang_decl_flags
unsigned declared_inline : 1;
unsigned not_really_extern : 1;
unsigned comdat : 1;
- unsigned dummy : 4;
+ unsigned needs_final_overrider : 1;
+ unsigned dummy : 3;
tree access;
tree context;
@@ -1075,6 +1076,10 @@ struct lang_decl
/* Nonzero for FUNCTION_DECL means that this member function
exists as part of an abstract class's interface. */
#define DECL_ABSTRACT_VIRTUAL_P(NODE) (DECL_LANG_SPECIFIC(NODE)->decl_flags.abstract_virtual)
+
+/* Nonzero for FUNCTION_DECL means that this member function
+ must be overridden by derived classes. */
+#define DECL_NEEDS_FINAL_OVERRIDER_P(NODE) (DECL_LANG_SPECIFIC(NODE)->decl_flags.needs_final_overrider)
/* Nonzero if allocated on permanent_obstack. */
#define LANG_DECL_PERMANENT(LANGDECL) ((LANGDECL)->decl_flags.permanent_attr)
diff -rup -x CVS -x *.o -x *.info* -x *.html* -x *.elc -x *.dvi -x *.orig -x *~ -x version.el egcs-980313.orig/gcc/cp/decl.c egcs-980313/gcc/cp/decl.c
--- egcs-980313.orig/gcc/cp/decl.c Thu Mar 5 09:20:45 1998
+++ egcs-980313/gcc/cp/decl.c Sat Mar 14 15:18:57 1998
@@ -2740,6 +2740,7 @@ duplicate_decls (newdecl, olddecl)
DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
DECL_ABSTRACT_VIRTUAL_P (newdecl) |= DECL_ABSTRACT_VIRTUAL_P (olddecl);
DECL_VIRTUAL_P (newdecl) |= DECL_VIRTUAL_P (olddecl);
+ DECL_NEEDS_FINAL_OVERRIDER_P (newdecl) |= DECL_NEEDS_FINAL_OVERRIDER_P (olddecl);
}
/* Deal with C++: must preserve virtual function table size. */
diff -rup -x CVS -x *.o -x *.info* -x *.html* -x *.elc -x *.dvi -x *.orig -x *~ -x version.el egcs-980313.orig/gcc/cp/typeck2.c egcs-980313/gcc/cp/typeck2.c
--- egcs-980313.orig/gcc/cp/typeck2.c Thu Mar 5 09:20:56 1998
+++ egcs-980313/gcc/cp/typeck2.c Sat Mar 14 15:20:58 1998
@@ -130,6 +130,29 @@ abstract_virtuals_error (decl, type)
tree type;
{
tree u = CLASSTYPE_ABSTRACT_VIRTUALS (type);
+ int has_abstract_virtuals, needs_final_overriders;
+ tree tu;
+
+ /* Count how many abstract methods need to be defined. */
+ for (has_abstract_virtuals = 0, tu = u; tu; tu = TREE_CHAIN (tu))
+ {
+ if (DECL_ABSTRACT_VIRTUAL_P (TREE_VALUE (tu))
+ && ! DECL_NEEDS_FINAL_OVERRIDER_P (TREE_VALUE (tu)))
+ {
+ has_abstract_virtuals = 1;
+ break;
+ }
+ }
+
+ /* Count how many virtual methods need a final overrider. */
+ for (needs_final_overriders = 0, tu = u; tu; tu = TREE_CHAIN (tu))
+ {
+ if (DECL_NEEDS_FINAL_OVERRIDER_P (TREE_VALUE (tu)))
+ {
+ needs_final_overriders = 1;
+ break;
+ }
+ }
if (decl)
{
@@ -151,19 +174,52 @@ abstract_virtuals_error (decl, type)
else if (TREE_CODE (decl) == FUNCTION_DECL)
cp_error ("invalid return type for function `%#D'", decl);
}
- else cp_error ("cannot allocate an object of type `%T'", type);
+ else
+ cp_error ("cannot allocate an object of type `%T'", type);
+
/* Only go through this once. */
if (TREE_PURPOSE (u) == NULL_TREE)
{
- error (" since the following virtual functions are abstract:");
TREE_PURPOSE (u) = error_mark_node;
- while (u)
+
+ if (has_abstract_virtuals)
+ error (" since the following virtual functions are abstract:");
+ tu = u;
+ while (tu)
+ {
+ if (DECL_ABSTRACT_VIRTUAL_P (TREE_VALUE (tu))
+ && ! DECL_NEEDS_FINAL_OVERRIDER_P (TREE_VALUE (tu)))
+ cp_error ("\t%#D", TREE_VALUE (tu));
+ tu = TREE_CHAIN (tu);
+ }
+
+ if (needs_final_overriders)
+ {
+ if (has_abstract_virtuals)
+ error (" and the following virtual functions need a final overrider:");
+ else
+ error (" since the following virtual functions need a final overrider:");
+ }
+ tu = u;
+ while (tu)
+ {
+ if (DECL_NEEDS_FINAL_OVERRIDER_P (TREE_VALUE (tu)))
+ cp_error ("\t%#D", TREE_VALUE (tu));
+ tu = TREE_CHAIN (tu);
+ }
+ }
+ else
+ {
+ if (has_abstract_virtuals)
{
- cp_error ("\t%#D", TREE_VALUE (u));
- u = TREE_CHAIN (u);
+ if (needs_final_overriders)
+ cp_error (" since type `%T' has abstract virtual functions and must override virtual functions", type);
+ else
+ cp_error (" since type `%T' has abstract virtual functions", type);
}
+ else
+ cp_error (" since type `%T' must override virtual functions", type);
}
- else cp_error (" since type `%T' has abstract virtual functions", type);
}
/* Print an error message for invalid use of a signature type.
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