http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46141
Summary: -fno-builtin-strstr changes __builtin_strstr
Product: gcc
Version: 4.6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: hjl.to...@gmail.com
I don't expect -fno-builtin-strstr to change the behavior
of __builtin_strstr. But I got
[...@gnu-6 asm-1]$ cat x.c
extern char *strstr(const char *, const char *) __asm ("my_strstr");
char *foo (const char *a, const char *b)
{
return __builtin_strstr (a, b);
}
[...@gnu-6 asm-1]$ make
/export/build/gnu/gcc/build-x86_64-linux/gcc/xgcc
-B/export/build/gnu/gcc/build-x86_64-linux/gcc/ -O -S x.c
/export/build/gnu/gcc/build-x86_64-linux/gcc/xgcc
-B/export/build/gnu/gcc/build-x86_64-linux/gcc/ -fno-builtin-strstr -O -S x.c
-o y.s
[...@gnu-6 asm-1]$ cat x.s
.file "x.c"
.text
.globl foo
.type foo, @function
foo:
.LFB0:
.cfi_startproc
subq $8, %rsp
.cfi_def_cfa_offset 16
call my_strstr
addq $8, %rsp
.cfi_def_cfa_offset 8
ret
.cfi_endproc
.LFE0:
.size foo, .-foo
.ident "GCC: (GNU) 4.6.0 20101021 (experimental)"
.section .note.GNU-stack,"",@progbits
[...@gnu-6 asm-1]$ cat y.s
.file "x.c"
.text
.globl foo
.type foo, @function
foo:
.LFB0:
.cfi_startproc
subq $8, %rsp
.cfi_def_cfa_offset 16
call strstr
addq $8, %rsp
.cfi_def_cfa_offset 8
ret
.cfi_endproc
.LFE0:
.size foo, .-foo
.ident "GCC: (GNU) 4.6.0 20101021 (experimental)"
.section .note.GNU-stack,"",@progbits
[...@gnu-6 asm-1]$
Shouldn't my_strstr be generated with -fno-builtin-strstr?
