https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109469
Bug ID: 109469
Summary: [13 regression] ICE: internal compiler error:
verify_flow_info failed (error: returns_twice call is
not first in basic block 2)
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: sjames at gcc dot gnu.org
Target Milestone: ---
Hit this when building xdvik-22.87.06 with 13.0.1 20230409 w/ checking.
```
x86_64-pc-linux-gnu-gcc -DHAVE_CONFIG_H -I. -I./gui -DPS_GS
-I/usr/include/freetype2 -I/usr/include/harfbuzz -I/usr/include/glib-2.0
-I/usr/lib64/glib-2.0/include -I/usr/include -Wimplicit -Wreturn-type -O2
-pipe -march=native -fdiagnostics-color=always -frecord-gcc-switches
-Wreturn-type -ggdb3 -Werror=implicit-function-declaration
-Werror=implicit-int -Wformat -Waddress -Warray-bounds -Wfree-nonheap-object
-Wimplicit-function-declaration -Wimplicit-int -Wincompatible-pointer-types
-Wint-conversion -Wint-to-pointer-cast -Wmain -Wnonnull -Wodr -Wparentheses
-Wreturn-type -Wsizeof-pointer-memaccess -Wstrict-aliasing -Wstring-compare
-Wuninitialized -Wunused-value -Wvarargs -c -o util.o util.c
util.c: In function ‘fork_process’:
util.c:988:1: error: returns_twice call is not first in basic block 25
988 | fork_process(const char *proc_name, Boolean redirect_stdout,
| ^~~~~~~~~~~~
pid_96 = vfork ();
during GIMPLE pass: slp
util.c:988:1: internal compiler error: verify_flow_info failed
0x7aa668 verify_flow_info()
/usr/src/debug/sys-devel/gcc-13.0.1_pre20230409-r1/gcc-13-20230409/gcc/cfghooks.cc:285
0x151e50d execute_function_todo
/usr/src/debug/sys-devel/gcc-13.0.1_pre20230409-r1/gcc-13-20230409/gcc/passes.cc:2110
0x1485fd1 do_per_function
/usr/src/debug/sys-devel/gcc-13.0.1_pre20230409-r1/gcc-13-20230409/gcc/passes.cc:1694
0x1485fd1 execute_todo
/usr/src/debug/sys-devel/gcc-13.0.1_pre20230409-r1/gcc-13-20230409/gcc/passes.cc:2152
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://bugs.gentoo.org/> for instructions.
```
