Fix asan_test.cc build on NetBSD

[krytarowski]

Summary

Include <stdarg.h> for variable argument list macros (va_list, va_start etc).

Add fallback definition of _LIBCPP_GET_C_LOCALE, this is required for
GNU libstdc++ compatibility. Define new macro SANITIZER_GET_C_LOCALE.
This value is currently required for FreeBSD and NetBSD for printf_l(3) tests.

Sponsored by <The NetBSD Foundation>

lib/asan/tests/asan_test.cc

 //===-- asan_test.cc ------------------------------------------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file is a part of AddressSanitizer, an address sanity checker.
 //
 //===----------------------------------------------------------------------===//
 #include "asan_test_utils.h"
 
 #include <errno.h>
+#include <stdarg.h>
+
+#ifdef _LIBCPP_GET_C_LOCALE
+#define SANITIZER_GET_C_LOCALE _LIBCPP_GET_C_LOCALE
+#else
+#if defined(__FreeBSD__)
+#define SANITIZER_GET_C_LOCALE 0
+#elif defined(__NetBSD__)
+#define SANITIZER_GET_C_LOCALE LC_C_LOCALE
+#endif
+#endif
 
 NOINLINE void *malloc_fff(size_t size) {
   void *res = malloc/**/(size); break_optimization(0); return res;}
 NOINLINE void *malloc_eee(size_t size) {
   void *res = malloc_fff(size); break_optimization(0); return res;}
 NOINLINE void *malloc_ddd(size_t size) {
   void *res = malloc_eee(size); break_optimization(0); return res;}
 NOINLINE void *malloc_ccc(size_t size) {
static int vsnprintf_l_wrapper(char *s, size_t n,
   int res = vsnprintf_l(s, n , l, format, va);
   va_end(va);
   return res;
 }
 
 TEST(AddressSanitizer, snprintf_l) {
   char buff[5];
   // Check that snprintf_l() works fine with Asan.
-  int res = snprintf_l(buff, 5,
-                       _LIBCPP_GET_C_LOCALE, "%s", "snprintf_l()");
+  int res = snprintf_l(buff, 5, SANITIZER_GET_C_LOCALE, "%s", "snprintf_l()");
   EXPECT_EQ(12, res);
   // Check that vsnprintf_l() works fine with Asan.
-  res = vsnprintf_l_wrapper(buff, 5,
-                            _LIBCPP_GET_C_LOCALE, "%s", "vsnprintf_l()");
+  res = vsnprintf_l_wrapper(buff, 5, SANITIZER_GET_C_LOCALE, "%s",
+                            "vsnprintf_l()");
   EXPECT_EQ(13, res);
 
-  EXPECT_DEATH(snprintf_l(buff, 10,
-                          _LIBCPP_GET_C_LOCALE, "%s", "snprintf_l()"),
-                "AddressSanitizer: stack-buffer-overflow");
-  EXPECT_DEATH(vsnprintf_l_wrapper(buff, 10,
-                                  _LIBCPP_GET_C_LOCALE, "%s", "vsnprintf_l()"),
-                "AddressSanitizer: stack-buffer-overflow");
+  EXPECT_DEATH(
+      snprintf_l(buff, 10, SANITIZER_GET_C_LOCALE, "%s", "snprintf_l()"),
+  EXPECT_DEATH(vsnprintf_l_wrapper(buff, 10, SANITIZER_GET_C_LOCALE, "%s",
+                                   "vsnprintf_l()"),
 }
 #endif