http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53425
Bug #: 53425
Summary: No warnings are given for -mno-sse
Classification: Unclassified
Product: gcc
Version: 4.8.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
AssignedTo: [email protected]
ReportedBy: [email protected]
CC: [email protected]
Target: x86-64
[hjl@gnu-mic-2 pr53383]$ cat z.c
typedef double __v2df __attribute__ ((__vector_size__ (16)));
extern __v2df x;
extern void bar (__v2df);
void
foo (void)
{
bar (x);
}
[hjl@gnu-mic-2 pr53383]$ make z.s
/export/build/gnu/gcc/build-x86_64-linux/gcc/xgcc
-B/export/build/gnu/gcc/build-x86_64-linux/gcc/ -O2 -mno-sse -S z.c
[hjl@gnu-mic-2 pr53383]$ cat z.s
.file "z.c"
.text
.p2align 4,,15
.globl foo
.type foo, @function
foo:
.LFB0:
.cfi_startproc
subq $40, %rsp
.cfi_def_cfa_offset 48
movq x(%rip), %rax
movq %rax, (%rsp)
movq x+8(%rip), %rax
movq %rax, 8(%rsp)
call bar
addq $40, %rsp
.cfi_def_cfa_offset 8
ret
.cfi_endproc
.LFE0:
.size foo, .-foo
.ident "GCC: (GNU) 4.8.0 20120519 (experimental)"
.section .note.GNU-stack,"",@progbits
[hjl@gnu-mic-2 pr53383]$
But we do issue a warning for 32-bit:
[hjl@gnu-mic-2 pr53383]$ /export/build/gnu/gcc/build-x86_64-linux/gcc/xgcc
-B/export/build/gnu/gcc/build-x86_64-linux/gcc/ -O2 -mno-sse -S z.c -m32
z.c: In function \u2018foo\u2019:
z.c:9:7: warning: SSE vector argument without SSE enabled changes the ABI
[enabled by default]
bar (x);
^
z.c:9:7: note: The ABI for passing parameters with 16-byte alignment has
changed in GCC 4.6
[hjl@gnu-mic-2 pr53383]$
I believe we should also issue a warning for 64-bit.
