[c/c++ (rfa)] fix 32455
Richard Henderson
rth@redhat.com
Wed Feb 6 18:04:00 GMT 2008
In fixing 32455, I agree with Richard Guenther that probably
the best way to fix the bug is simply to prevent users from
re-declaring __builtin_ functions with different signatures.
Indeed, the easiest way appears to be to prevent them from
doing pretty much anything with the __builtin_ namespace.
This is an RFA for the C++ side, because while the testcase
I have appears to work, I've no idea what other kind of side
effects may be involved on that side.
r~
* c-common.c (builtin_name_p): New.
(disable_builtin_function, def_builtin_1): Use it.
* c-common.h (builtin_name_p): Declare.
* c-decl.c (grokdeclarator): Deny declarations w/ builtin_name_p.
(grokfield): Create an error field when grokdeclarator fails.
cp/
* decl.c (grokdeclarator): Deny declarations w/ builtin_name_p.
testsuite/
* g++.old-deja/g++.law/operators24.C: Remove.
* gcc.dg/torture/builtin-convert-3.c: Don't declare __builtin's.
* gcc.dg/torture/builtin-nonneg-1.c: Likewise.
* gcc.dg/pr32455-1.c, gcc.dg/pr32455-2.c: New.
--- gcc/c-common.c (revision 132159)
+++ gcc/c-common.c (local)
@@ -3966,13 +3966,19 @@ static disabled_builtin *disabled_builti
static bool builtin_function_disabled_p (const char *);
+bool
+builtin_name_p (const char *name)
+{
+ return strncmp (name, "__builtin_", strlen ("__builtin_")) == 0;
+}
+
/* Disable a built-in function specified by -fno-builtin-NAME. If NAME
begins with "__builtin_", give an error. */
void
disable_builtin_function (const char *name)
{
- if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
+ if (builtin_name_p (name))
error ("cannot disable built-in function %qs", name);
else
{
@@ -4019,9 +4025,7 @@ def_builtin_1 (enum built_in_function fn
if (fntype == error_mark_node)
return;
- gcc_assert ((!both_p && !fallback_p)
- || !strncmp (name, "__builtin_",
- strlen ("__builtin_")));
+ gcc_assert ((!both_p && !fallback_p) || builtin_name_p (name));
libname = name + strlen ("__builtin_");
decl = add_builtin_function (name, fntype, fncode, fnclass,
--- gcc/c-common.h (revision 132159)
+++ gcc/c-common.h (local)
@@ -649,6 +649,7 @@ extern const struct attribute_spec c_com
extern tree (*make_fname_decl) (tree, int);
+extern bool builtin_name_p (const char *);
extern tree identifier_global_value (tree);
extern void record_builtin_type (enum rid, const char *, tree);
extern tree build_void_list_node (void);
--- gcc/c-decl.c (revision 132159)
+++ gcc/c-decl.c (local)
@@ -4028,9 +4028,14 @@ grokdeclarator (const struct c_declarato
name = "type name";
}
+ if (name && builtin_name_p (name))
+ {
+ error ("%qs is a reserved name", name);
+ return 0;
+ }
+
/* A function definition's declarator must have the form of
a function declarator. */
-
if (funcdef_flag && !funcdef_syntax)
return 0;
@@ -5449,8 +5454,13 @@ grokfield (struct c_declarator *declarat
width ? &width : NULL, decl_attrs,
DEPRECATED_NORMAL);
- finish_decl (value, NULL_TREE, NULL_TREE);
- DECL_INITIAL (value) = width;
+ if (value == 0)
+ value = build_decl (FIELD_DECL, NULL_TREE, error_mark_node);
+ else
+ {
+ finish_decl (value, NULL_TREE, NULL_TREE);
+ DECL_INITIAL (value) = width;
+ }
return value;
}
--- gcc/cp/decl.c (revision 132159)
+++ gcc/cp/decl.c (local)
@@ -7562,6 +7562,12 @@ grokdeclarator (const cp_declarator *dec
break;
}
+ if (name && builtin_name_p (name))
+ {
+ error ("%qs is a reserved name", name);
+ return error_mark_node;
+ }
+
/* [dcl.fct.edf]
The declarator in a function-definition shall have the form
--- gcc/testsuite/g++.old-deja/g++.law/operators24.C (revision 132159)
+++ gcc/testsuite/g++.old-deja/g++.law/operators24.C (local)
@@ -1,14 +0,0 @@
-// { dg-do assemble }
-// GROUPS passed operators
-// opr-new file
-// From: rwave!myersn%rwave.roguewave@cs.orst.edu (Nathan Myers)
-// Date: Wed, 16 Dec 92 11:55 PST
-// Subject: 2.3.2: friend decl breaks member op new
-// Message-ID: <m0n24qP-0000GmC@rwave.roguewave.com>
-
-#include <stddef.h>
-struct Link {
- void* operator new(size_t, int);
- friend void* __builtin_new(size_t); // This declaration triggers the bug
-};
-void f() { new(2) Link; }
--- gcc/testsuite/gcc.dg/torture/builtin-convert-3.c (revision 132159)
+++ gcc/testsuite/gcc.dg/torture/builtin-convert-3.c (local)
@@ -20,7 +20,6 @@
argument is a narrower type (perhaps implicitly) cast to a wider
one. */
#define INNER_CAST1(MATHFN, RET) \
- PROTOTYPE1_RET (MATHFN, RET); \
extern void link_failure_inner_##MATHFN##l_##MATHFN(void); \
extern void link_failure_inner_##MATHFN##l_##MATHFN##f(void); \
extern void link_failure_inner_##MATHFN##_##MATHFN##f(void); \
@@ -37,6 +36,10 @@
&& MATHFN(f1) != MATHFN##f(f1)) \
link_failure_inner_##MATHFN##_##MATHFN##f()
+#define INNER_CAST2(MATHFN, RET) \
+ PROTOTYPE1_RET (MATHFN, RET) \
+ INNER_CAST1 (MATHFN, RET)
+
void __attribute__ ((__noinline__)) test (double d1, float f1)
{
#ifdef __OPTIMIZE__
@@ -46,10 +49,10 @@ void __attribute__ ((__noinline__)) test
INNER_CAST1 (__builtin_llceil, long long);
INNER_CAST1 (__builtin_lfloor, long);
INNER_CAST1 (__builtin_llfloor, long long);
- INNER_CAST1 (lround, long);
- INNER_CAST1 (llround, long long);
- INNER_CAST1 (lrint, long);
- INNER_CAST1 (llrint, long long);
+ INNER_CAST2 (lround, long);
+ INNER_CAST2 (llround, long long);
+ INNER_CAST2 (lrint, long);
+ INNER_CAST2 (llrint, long long);
#endif /* HAVE_C99_RUNTIME */
#endif /* __OPTIMIZE__ */
}
--- gcc/testsuite/gcc.dg/torture/builtin-nonneg-1.c (revision 132159)
+++ gcc/testsuite/gcc.dg/torture/builtin-nonneg-1.c (local)
@@ -55,6 +55,11 @@ void test(double d1, double d2, float f1
if (signbit(FN(d1)) || signbitf(FN##f(f1)) || signbitl(FN##l(ld1))) \
link_failure_##FN()
+#define _ITEST1(FN) \
+ extern void link_failure_##FN (void); \
+ if (signbit(FN(d1)) || signbitf(FN##l(f1)) || signbitl(FN##ll(ld1))) \
+ link_failure_##FN()
+
#define ITEST1(FN) \
extern void link_failure_##FN (void); IPROTOTYPE(FN) \
if (signbit(FN(d1)) || signbitf(FN##l(f1)) || signbitl(FN##ll(ld1))) \
@@ -74,8 +79,8 @@ void test(double d1, double d2, float f1
TEST1 (pow10);
TEST1 (sqrt);
ITEST1 (ffs);
- ITEST1 (__builtin_parity);
- ITEST1 (__builtin_popcount);
+ _ITEST1 (__builtin_parity);
+ _ITEST1 (__builtin_popcount);
/* These are nonnegative if the first argument is. */
#define ARG1TEST1(FN) \
@@ -85,6 +90,12 @@ void test(double d1, double d2, float f1
link_failure_##FN()
/* Same, but allow specifying the return type. */
+#define _ARG1TEST1_RTYPE(FN,RTYPE) \
+ extern void link_failure_##FN (void); \
+ if (signbit(FN(fabs(d1))) || signbitf(FN##f(fabsf(f1))) \
+ || signbitl(FN##l(fabsl(ld1)))) \
+ link_failure_##FN()
+
#define ARG1TEST1_RTYPE(FN,RTYPE) \
extern void link_failure_##FN (void); PROTOTYPE_RTYPE(FN,RTYPE) \
if (signbit(FN(fabs(d1))) || signbitf(FN##f(fabsf(f1))) \
@@ -144,12 +155,12 @@ void test(double d1, double d2, float f1
ARG1TEST1 (floor);
ARG1TEST2 (fmod);
ARG1TEST2_A2INT (ldexp, int);
- ARG1TEST1_RTYPE (__builtin_llceil, long long);
- ARG1TEST1_RTYPE (__builtin_llfloor, long long);
+ _ARG1TEST1_RTYPE (__builtin_llceil, long long);
+ _ARG1TEST1_RTYPE (__builtin_llfloor, long long);
ARG1TEST1_RTYPE (llrint, long long);
ARG1TEST1_RTYPE (llround, long long);
- ARG1TEST1_RTYPE (__builtin_lceil, long);
- ARG1TEST1_RTYPE (__builtin_lfloor, long);
+ _ARG1TEST1_RTYPE (__builtin_lceil, long);
+ _ARG1TEST1_RTYPE (__builtin_lfloor, long);
ARG1TEST1_RTYPE (lrint, long);
ARG1TEST1_RTYPE (lround, long);
/* The modf* functions aren't ever "const" or "pure" even with
--- gcc/testsuite/gcc.dg/pr32455-1.c (revision 132159)
+++ gcc/testsuite/gcc.dg/pr32455-1.c (local)
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+
+typedef double* va_list;
+
+void __builtin_va_start(va_list, ...); /* { dg-error "reserved" } */
+
+void foo(const char* s, ...)
+{
+ va_list v;
+ __builtin_va_start(v, s); /* { dg-error "" } */
+}
--- gcc/testsuite/gcc.dg/pr32455-2.c (revision 132159)
+++ gcc/testsuite/gcc.dg/pr32455-2.c (local)
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+
+struct __builtin_struct
+{
+ int x;
+ int __builtin_field; /* { dg-error "reserved" } */
+};
+
+int __builtin_var = 1; /* { dg-error "reserved" } */
+
+extern void __builtin_func_decl (void); /* { dg-error "reserved" } */
+
+/* ??? We get multiple errors here, cause we forget it's supposed
+ to be a function type we're declaring... */
+void __builtin_func_defn (void) /* { dg-error "" } */
+{
+}
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