<rdar://problem/13479214> Make Clang's <stddef.h> robust against system headers defining size_t/ptrdiff_t/wchar_t.

Clang's <stddef.h> provides definitions for the C standard library
types size_t, ptrdiff_t, and wchar_t. However, the system's C standard
library headers tend to provide the same typedefs, and the two
generally avoid each other using the macros
_SIZE_T/_PTRDIFF_T/_WCHAR_T. With modules, however, we need to see
*all* of the places where these types are defined, so provide the
typedefs (ignoring the macros) when modules are enabled.

llvm-svn: 177686

4 files changed, 24 insertions, 0 deletions

diff --git a/clang/test/Modules/Inputs/StdDef/module.map b/clang/test/Modules/Inputs/StdDef/module.map
new file mode 100644
index 00000000000..69c69eac35b
--- /dev/null
+++ b/clang/test/Modules/Inputs/StdDef/module.map
@@ -0,0 +1,11 @@
+module StdDef {
+  module SizeT {
+    header "size_t.h"
+    export *
+  }
+
+  module Other {
+    header "other.h"
+    export *
+  }
+}
diff --git a/clang/test/Modules/Inputs/StdDef/other.h b/clang/test/Modules/Inputs/StdDef/other.h
new file mode 100644
index 00000000000..f29f6366cc6
--- /dev/null
+++ b/clang/test/Modules/Inputs/StdDef/other.h
@@ -0,0 +1,2 @@
+#include <stddef.h>
+
diff --git a/clang/test/Modules/Inputs/StdDef/size_t.h b/clang/test/Modules/Inputs/StdDef/size_t.h
new file mode 100644
index 00000000000..9ac61c5e0d7
--- /dev/null
+++ b/clang/test/Modules/Inputs/StdDef/size_t.h
@@ -0,0 +1,4 @@
+#ifndef _SIZE_T
+#define _SIZE_T
+typedef __SIZE_TYPE__ size_t;
+#endif
diff --git a/clang/test/Modules/stddef.m b/clang/test/Modules/stddef.m
new file mode 100644
index 00000000000..83f73f9d33a
--- /dev/null
+++ b/clang/test/Modules/stddef.m
@@ -0,0 +1,7 @@
+@import StdDef.Other;
+
+size_t getSize();
+
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -I %S/Inputs/StdDef %s -verify
+// expected-no-diagnostics