[compiler-rt] [compiler-rt] Avoid defining _KERNEL on FreeBSD (PR #143116)

[Jessica Clarke via llvm-commits]

https://github.com/jrtc27 created https://github.com/llvm/llvm-project/pull/143116

Defining _KERNEL is a hack that can cause all kinds of breakage if
you're not careful, since the actual environment is not a kernel build,
and so should be avoided. Since FreeBSD 12 (MFC'ed for 11.3) you can
define _WANT_SYSVSHM_INTERNALS to expose shminfo (and various other
things) to userspace, so use that instead.


>From bb30a782d6e6f5716b736416a6848be111767c11 Mon Sep 17 00:00:00 2001
From: Jessica Clarke <jrtc27 at jrtc27.com>
Date: Fri, 6 Jun 2025 12:39:14 +0100
Subject: [PATCH] [compiler-rt] Avoid defining _KERNEL on FreeBSD

Defining _KERNEL is a hack that can cause all kinds of breakage if
you're not careful, since the actual environment is not a kernel build,
and so should be avoided. Since FreeBSD 12 (MFC'ed for 11.3) you can
define _WANT_SYSVSHM_INTERNALS to expose shminfo (and various other
things) to userspace, so use that instead.
---
 .../lib/sanitizer_common/sanitizer_platform_limits_freebsd.cpp | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_freebsd.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_freebsd.cpp
index 4940062eeae47..8e83ef9ae61df 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_freebsd.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_freebsd.cpp
@@ -87,9 +87,8 @@
 #include <wchar.h>
 #include <wordexp.h>
 
-#define _KERNEL  // to declare 'shminfo' structure
+#define _WANT_SYSVSHM_INTERNALS  // to declare 'shminfo' structure
 #include <sys/shm.h>
-#undef _KERNEL
 
 #undef IOC_DIRMASK