[compiler-rt] [tsan] Fix build for FreeBSD and NetBSD after 0784b1eefa36 (PR #79019)

[Dimitry Andric via llvm-commits]

https://github.com/DimitryAndric created https://github.com/llvm/llvm-project/pull/79019

In 0784b1eefa36 some code for re-execution was moved to `ReExecIfNeeded()`, but also extended with a few Linux-only features. This leads to compile errors on FreeBSD, or other non-Linux platforms:

    compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp:247:25: error: use of undeclared identifier 'personality'
      247 |   int old_personality = personality(0xffffffff);
          |                         ^
    compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp:249:54: error: use of undeclared identifier 'ADDR_NO_RANDOMIZE'
      249 |       (old_personality != -1) && ((old_personality & ADDR_NO_RANDOMIZE) == 0);
          |                                                      ^
    compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp:281:46: error: use of undeclared identifier 'ADDR_NO_RANDOMIZE'
      281 |       CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1);
          |                                              ^

Surround the affected part with a `#if SANITIZER_LINUX` block for now.

>From 8d0155257cd40c57f0a475cfe06efc1eb544ce9e Mon Sep 17 00:00:00 2001
From: Dimitry Andric <dimitry at andric.com>
Date: Mon, 22 Jan 2024 18:31:10 +0100
Subject: [PATCH] [tsan] Fix build for FreeBSD and NetBSD after 0784b1eefa36

In 0784b1eefa36 some code for re-execution was moved to
`ReExecIfNeeded()`, but also extended with a few Linux-only features.
This leads to compile errors on FreeBSD, or other non-Linux platforms:

    compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp:247:25: error: use of undeclared identifier 'personality'
      247 |   int old_personality = personality(0xffffffff);
          |                         ^
    compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp:249:54: error: use of undeclared identifier 'ADDR_NO_RANDOMIZE'
      249 |       (old_personality != -1) && ((old_personality & ADDR_NO_RANDOMIZE) == 0);
          |                                                      ^
    compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp:281:46: error: use of undeclared identifier 'ADDR_NO_RANDOMIZE'
      281 |       CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1);
          |                                              ^

Surround the affected part with a `#if SANITIZER_LINUX` block for now.
---
 compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp b/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp
index 9a66a7feb5b395..0d0b1aba1f852a 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp
@@ -243,12 +243,13 @@ static void ReExecIfNeeded() {
     reexec = true;
   }
 
+#    if SANITIZER_LINUX
   // ASLR personality check.
   int old_personality = personality(0xffffffff);
   bool aslr_on =
       (old_personality != -1) && ((old_personality & ADDR_NO_RANDOMIZE) == 0);
 
-#    if SANITIZER_ANDROID && (defined(__aarch64__) || defined(__x86_64__))
+#      if SANITIZER_ANDROID && (defined(__aarch64__) || defined(__x86_64__))
   // After patch "arm64: mm: support ARCH_MMAP_RND_BITS." is introduced in
   // linux kernel, the random gap between stack and mapped area is increased
   // from 128M to 36G on 39-bit aarch64. As it is almost impossible to cover
@@ -261,7 +262,7 @@ static void ReExecIfNeeded() {
     CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1);
     reexec = true;
   }
-#    endif
+#      endif
 
   if (reexec) {
     // Don't check the address space since we're going to re-exec anyway.
@@ -288,6 +289,7 @@ static void ReExecIfNeeded() {
       Die();
     }
   }
+#    endif  // SANITIZER_LINUX
 
   if (reexec)
     ReExec();