[Sanitizers] Secondary allocator respects allocator_may_return_null=1.

Summary:
Context: https://github.com/google/sanitizers/issues/740.

Making secondary allocator to respect allocator_may_return_null=1 flag
and return nullptr when "out of memory" happens.

More changes in primary allocator and operator new will follow.

Reviewers: eugenis

Subscribers: kubamracek, llvm-commits

Differential Revision: https://reviews.llvm.org/D34243

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@305569 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 3 insertions, 0 deletions

diff --git a/lib/sanitizer_common/sanitizer_common.h b/lib/sanitizer_common/sanitizer_common.h
index 79ee6873b..875a46009 100644
--- a/lib/sanitizer_common/sanitizer_common.h
+++ b/lib/sanitizer_common/sanitizer_common.h
@@ -85,6 +85,9 @@ INLINE void *MmapOrDieQuietly(uptr size, const char *mem_type) {
   return MmapOrDie(size, mem_type, /*raw_report*/ true);
 }
 void UnmapOrDie(void *addr, uptr size);
+// Behaves just like MmapOrDie, but tolerates out of memory condition, in that
+// case returns nullptr.
+void *MmapOrDieOnFatalError(uptr size, const char *mem_type);
 void *MmapFixedNoReserve(uptr fixed_addr, uptr size,
                          const char *name = nullptr);
 void *MmapNoReserveOrDie(uptr size, const char *mem_type);