http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47409
Francesco Zappa Nardelli <francesco.zappa.nardelli at gmail dot com> changed:
What |Removed |Added
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CC| |francesco.zappa.nardelli@gm
| |ail.com
--- Comment #16 from Francesco Zappa Nardelli <francesco.zappa.nardelli at
gmail dot com> ---
Dear all
a possibly related issue. Consider
struct S1 {
long f;
};
volatile struct S1 g;
struct S1 func_1 () {
return g;
}
void main () {
func_1 ();
}
This program, if compiled with a recent gcc svn:
$ gcc -v
Target: x86_64-unknown-linux-gnu
gcc version 4.9.0 20130625 (experimental) (GCC)
correctly loads the long at g.f at -O0. However the assembly generated at -O2:
func_1:
movq g(%rip), %rax
ret
main:
rep; ret
does not perform the volatile load access, which, as far as I understand, is
incorrect.
-francesco
