[Bug target/37216] [cygming] Invalid alignment for SSE store to .comm data generated with -O3

[brian at dessent dot net]

------- Comment #21 from brian at dessent dot net  2008-09-29 20:06 -------
Subject: Re:  [cygming] Invalid alignment for SSE store to 
 .comm data generated with -O3

This is an example of what I'm talking about: the bar() function is
optimized away to simply "return 0" because the compiler assumes the
alignment is correct without having to actually emit the code to check
it:

$ echo 'char foo[1] __attribute__((aligned(16))); int bar() {
if((int)foo % 16) return 1; else return 0; }' | i686-pc-mingw32-gcc -x c
- -S -o - -fomit-frame-pointer
        .file   ""
        .text
.globl _bar
        .def    _bar;   .scl    2;      .type   32;     .endef
_bar:
        movl    $0, %eax
        ret
        .comm   _foo, 16         # 1


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37216