Hi!
The 3 functions in builtins.c that dispatch builtin folding give up
if avoid_folding_inline_builtin (fndecl) returns true, because we
want to wait with those functions until they are inlined (which for
-D_FORTIFY_SOURCE contains security checks). Unfortunately
gimple_fold_builtin calls fold_builtin_str* etc. directly and thus bypasses
this check. This didn't show up often because most of the inlines
have __restrict arguments and restrict casts weren't considered useless.
Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux,
preapproved by richi on IRC, will commit to trunk momentarily.
2011-10-06 Jakub Jelinek <ja...@redhat.com>
* tree.h (avoid_folding_inline_builtin): New prototype.
* builtins.c (avoid_folding_inline_builtin): No longer static.
* gimple-fold.c (gimple_fold_builtin): Give up if
avoid_folding_inline_builtin returns true.
--- gcc/tree.h.jj 2011-10-03 14:27:50.000000000 +0200
+++ gcc/tree.h 2011-10-06 13:26:32.000000000 +0200
@@ -5352,6 +5352,7 @@ fold_build_pointer_plus_hwi_loc (locatio
fold_build_pointer_plus_hwi_loc (UNKNOWN_LOCATION, p, o)
/* In builtins.c */
+extern bool avoid_folding_inline_builtin (tree);
extern tree fold_call_expr (location_t, tree, bool);
extern tree fold_builtin_fputs (location_t, tree, tree, bool, bool, tree);
extern tree fold_builtin_strcpy (location_t, tree, tree, tree, tree);
--- gcc/builtins.c.jj 2011-10-05 08:13:55.000000000 +0200
+++ gcc/builtins.c 2011-10-06 13:25:39.000000000 +0200
@@ -10360,7 +10360,7 @@ fold_builtin_varargs (location_t loc, tr
been inlined, otherwise e.g. -D_FORTIFY_SOURCE checking
might not be performed. */
-static bool
+bool
avoid_folding_inline_builtin (tree fndecl)
{
return (DECL_DECLARED_INLINE_P (fndecl)
--- gcc/gimple-fold.c.jj 2011-10-06 09:14:17.000000000 +0200
+++ gcc/gimple-fold.c 2011-10-06 13:29:08.000000000 +0200
@@ -828,6 +828,11 @@ gimple_fold_builtin (gimple stmt)
if (DECL_BUILT_IN_CLASS (callee) == BUILT_IN_MD)
return NULL_TREE;
+ /* Give up for always_inline inline builtins until they are
+ inlined. */
+ if (avoid_folding_inline_builtin (callee))
+ return NULL_TREE;
+
/* If the builtin could not be folded, and it has no argument list,
we're done. */
nargs = gimple_call_num_args (stmt);
Jakub
