https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101727
Bug ID: 101727
Summary: invalid symbol redefinition when -O2 enabled
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: inline-asm
Assignee: unassigned at gcc dot gnu.org
Reporter: zhan3299 at purdue dot edu
Target Milestone: ---
Following code can be successfully compiled with O0 optimization enabled, but
not O2.
Example code:
---
#include <stdio.h>
int func() {
int filter;
asm volatile(
" leaq _filter(%%rip), %%rax\n"
" jmp _out\n"
"_filter:\n"
".ascii \"\\040\"\n"
"_out:"
: "=rax"(filter)
:
:);
return filter;
}
int main() {
printf("%#x", func());
return 0;
}
---
Error messages of O2:
---
ASM generation compiler returned: 0
<source>: Assembler messages:
<source>:7: Error: symbol `_filter' is already defined
<source>:9: Error: symbol `_out' is already defined
Execution build compiler returned: 1
---
It affects 11.0, 12.0.
O2: https://godbolt.org/z/j9xG96fxW
O0: https://godbolt.org/z/b4TqddvYh
