Recommit r282692: [libc++abi] Use fallback_malloc to allocate __cxa_eh_globals in case of dynamic memory exhaustion.

Throwing an exception for the first time may lead to call calloc to
allocate memory for __cxa_eh_globals. If the memory pool is exhausted
at that moment, it results in abnormal termination of the program.

This patch addresses the issue by using fallback_malloc in that case.

In this revision, some restrictions were added into the test to not
run it in unsuitable environments.

Differential Revision: https://reviews.llvm.org/D17815



git-svn-id: https://llvm.org/svn/llvm-project/libcxxabi/trunk@283531 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 31 insertions, 0 deletions

diff --git a/src/fallback_malloc.h b/src/fallback_malloc.h
new file mode 100644
index 0000000..1078442
--- /dev/null
+++ b/src/fallback_malloc.h
@@ -0,0 +1,31 @@
+//===------------------------- fallback_malloc.h --------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _FALLBACK_MALLOC_H
+#define _FALLBACK_MALLOC_H
+
+#include <cstddef> // for size_t
+
+namespace __cxxabiv1 {
+
+#pragma GCC visibility push(hidden)
+
+// Allocate some memory from _somewhere_
+void * __malloc_with_fallback(size_t size);
+
+// Allocate and zero-initialize memory from _somewhere_
+void * __calloc_with_fallback(size_t count, size_t size);
+
+void __free_with_fallback(void *ptr);
+
+#pragma GCC visibility pop
+
+} // namespace __cxxabiv1
+
+#endif