diff options
Diffstat (limited to 'tools/build/cross-build/include/linux/sys')
| -rw-r--r-- | tools/build/cross-build/include/linux/sys/wait.h | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/tools/build/cross-build/include/linux/sys/wait.h b/tools/build/cross-build/include/linux/sys/wait.h index 2721218a83d4..ca17bfae9b8a 100644 --- a/tools/build/cross-build/include/linux/sys/wait.h +++ b/tools/build/cross-build/include/linux/sys/wait.h @@ -27,5 +27,21 @@ #pragma once +/* + * glibc's sys/wait.h and stdlib.h both define various wait-related constants, + * depending on __USE_XOPEN(2K8) and if the other header has been included. + * Since they each probe the other's include guard to determine that, there is + * a window between a header defining its include guard and checking for the + * other's within which, if the other is included for the first time, they both + * believe the other has already defined the relevant macros etc, and so + * neither ends up doing so. This was not previously hit, and is still not hit + * when using glibc normally (though seems extremely fragile). However, as of + * glibc 2.34, signal.h, included by sys/wait, includes a new bits/sigstksz, + * which in turn includes unistd.h (when _SC_SIGSTKSZ_SOURCE is defined, which + * is implied by _GNU_SOURCE), which we wrap and include stdlib.h from, + * creating the exact aforementioned situation that breaks. Thus, forcefully + * include stdlib.h first whenever sys/wait.h is as a workaround, since that + * way round still works. + */ #include <stdlib.h> #include_next <sys/wait.h> |