From 237d4c2eabc339f18bb9fc2d533e163357976507 Mon Sep 17 00:00:00 2001
From: Filipe Cabecinhas <me@filcab.net>
Date: Fri, 15 Dec 2017 17:30:50 +0000
Subject: [PATCH] [ubsan-minimal] Add a path for non-POSIX (and bare-metal) use
 of the library

Summary:
Hook on -DKERNEL_USE (which is also used in lib/builtins) to not import
strlen and not rely on write() being implemented with the stderr on fd 2.

With this, the only requirements to use this library are:
  - "Good enough" std::atomic<void*> and std::atomic<int>
  - abort() being implemented
  - ubsan_message(const char*) being implemented

Reviewers: eugenis

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D39791

llvm-svn: 320831
---
 compiler-rt/lib/ubsan_minimal/ubsan_minimal_handlers.cc | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/compiler-rt/lib/ubsan_minimal/ubsan_minimal_handlers.cc b/compiler-rt/lib/ubsan_minimal/ubsan_minimal_handlers.cc
index 92b673d9eb8a..5a5675c983fe 100644
--- a/compiler-rt/lib/ubsan_minimal/ubsan_minimal_handlers.cc
+++ b/compiler-rt/lib/ubsan_minimal/ubsan_minimal_handlers.cc
@@ -5,9 +5,14 @@
 #include <string.h>
 #include <unistd.h>
 
+#ifdef KERNEL_USE
+extern "C" void ubsan_message(const char *msg);
+static void message(const char *msg) { ubsan_message(msg); }
+#else
 static void message(const char *msg) {
   write(2, msg, strlen(msg));
 }
+#endif
 
 static const int kMaxCallerPcs = 20;
 static __sanitizer::atomic_uintptr_t caller_pcs[kMaxCallerPcs];