[libunwind] Drop the dependency on <algorithm>, add placement new inline

We haven't eliminated C++ library dependency altogether in D57251,
UnwindCursor.hpp had an unused dependency on <algorithm> which was
pulling in other C++ headers. Removing that dependency also revealed
(correctly) that we need our own global placement new declaration. Now
libunwind should be independent of the C++ library.

Differential Revision: https://reviews.llvm.org/D57262

llvm-svn: 352384

1 files changed, 4 insertions, 4 deletions

diff --git a/libunwind/src/libunwind.cpp b/libunwind/src/libunwind.cpp
index a2496a06de9..cfa9112a633 100644
--- a/libunwind/src/libunwind.cpp
+++ b/libunwind/src/libunwind.cpp
@@ -11,10 +11,6 @@
 
 #include <libunwind.h>
 
-#ifndef NDEBUG
-#include <cstdlib> // getenv
-#endif
-
 #include "libunwind_ext.h"
 #include "config.h"
 
@@ -27,6 +23,10 @@
 
 using namespace libunwind;
 
+// libunwind does not and should not depend on C++ library which means that we
+// need our own declaration of global placement new.
+void *operator new(size_t, void*);
+
 /// internal object to represent this processes address space
 LocalAddressSpace LocalAddressSpace::sThisAddressSpace;