3.12.0b3 build issue: 'O_CLOEXEC' undeclared in sysmodule.c

[lmunch]

I am building Python 3.12.0b3 (3.11.X builds fine) on CentOS 5 using glibc-2.5 and gcc-4.8.5 and I encounter this build error:

gcc-4.8 -std=gnu11 -pthread -c -fno-strict-overflow -Wsign-compare -DNDEBUG -g -O3 -Wall -std=c11 -Wextra -Wno-unused-parameter -Wno-missing-field-initializers -Wstrict-prototypes -Werror=implicit-function-declaration -fvisibility=hidden -I./Include/internal -I. -I./Include -fPIC -DPy_BUILD_CORE
-DABIFLAGS='""'
-DMULTIARCH="x86_64-linux-gnu"
-o Python/sysmodule.o ./Python/sysmodule.c
./Python/sysmodule.c: In function 'PyUnstable_PerfMapState_Init':
./Python/sysmodule.c:2280:62: error: 'O_CLOEXEC' undeclared (first use in this function)
int flags = O_WRONLY | O_CREAT | O_APPEND | O_NOFOLLOW | O_CLOEXEC;
^
./Python/sysmodule.c:2280:62: note: each undeclared identifier is reported only once for each function it appears in
make: *** [Python/sysmodule.o] Error 1

Perhaps there is a missing #ifdef O_CLOEXEC in ./Python/sysmodule.c?

Thanks

Linked PRs

• gh-106118: Add O_CLOEXEC preprocessor guard #106120
• [3.12] gh-106118: Add O_CLOEXEC preprocessor guard (GH-106120) #106199

[erlend-aasland]

It looks like the other usages of O_CLOEXEC are guarded by preprocessor conditionals. AFAICS, we should do the same here.