https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120973
Bug ID: 120973
Summary: ICE on x86_64-linux-gnu: verify_flow_info failed with
naked attribute: wrong insn in the fallthru edge
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: rtl-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: jiangchangwu at smail dot nju.edu.cn
Target Milestone: ---
Compiler Explorer: https://gcc.godbolt.org/z/nGrb6dP8e
*******************************************************************************
gcc version:
Using built-in specs.
COLLECT_GCC=gcc-trunk
COLLECT_LTO_WRAPPER=/home/software/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/16.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc/configure --disable-multilib --disable-bootstrap
--enable-languages=c,c++ --prefix=/home/software/gcc-trunk --enable-coverage
--disable-werror --enable-checking=yes
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 16.0.0 20250613 (experimental) (GCC)
*******************************************************************************
Program:
$ cat mutant.c
__attribute__((naked)) int a() {
static int b;
if (b) {
&&c;
&&d;
b = 1;
}
goto * 0;
c:
return 1;
d:
return 2;
}
void main() {}
*******************************************************************************
Command Lines:
$ gcc -O2 mutant.c
mutant.c: In function 'a':
mutant.c:13:1: error: verify_flow_info: Incorrect fallthru 8->9
13 | }
| ^
mutant.c:13:1: error: wrong insn in the fallthru edge
(barrier 56 53 58)
during RTL pass: bbro
mutant.c:13:1: internal compiler error: verify_flow_info failed
0x5554b38 internal_error(char const*, ...)
../../gcc/gcc/diagnostic-global-context.cc:517
0x138dea2 verify_flow_info()
../../gcc/gcc/cfghooks.cc:287
0x137cb0c checking_verify_flow_info()
../../gcc/gcc/cfghooks.h:214
0x13c7a39 cfg_layout_finalize()
../../gcc/gcc/cfgrtl.cc:4631
0x4bbf965 execute
../../gcc/gcc/bb-reorder.cc:2683
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
