https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100416
Bug ID: 100416
Summary: profiledbootstrap broken on (at least) arm and aarch64
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: bootstrap
Assignee: unassigned at gcc dot gnu.org
Reporter: acoplan at gcc dot gnu.org
Target Milestone: ---
It seems that -fprofile-generate tickles extra -Wmaybe-uninitialized warnings,
which in turn is causing profiledbootstrap to fail on (at least) arm and
aarch64.
For example, one of the failures is building simplify-rtx.c (here on aarch64):
In file included from /home/alecop01/toolchain/src/gcc/gcc/coretypes.h:472,
from /home/alecop01/toolchain/src/gcc/gcc/simplify-rtx.c:23:
/home/alecop01/toolchain/src/gcc/gcc/machmode.h: In function ‘rtx_def*
simplify_const_binary_operation(rtx_code, machine_mode, rtx, rtx)’:
/home/alecop01/toolchain/src/gcc/gcc/machmode.h:569:25: error: ‘*(unsigned
int*)((char*)&int_mode + offsetof(scalar_int_mode, scalar_int_mode::m_mode))’
may be used uninitialized in this function [-Werror=maybe-uninitialized]
569 | return mode_precision[mode];
| ^~~~
/home/alecop01/toolchain/src/gcc/gcc/simplify-rtx.c:4733:19: note: ‘*(unsigned
int*)((char*)&int_mode + offsetof(scalar_int_mode, scalar_int_mode::m_mode))’
was declared here
4733 | scalar_int_mode int_mode;
| ^~~~~~~~
cc1plus: all warnings being treated as errors
Makefile:1142: recipe for target 'simplify-rtx.o' failed
