commit 6680738a18fc219de2e4f7be1d53e4fb251f1166
Author: Siddhesh Poyarekar <siddhesh@redhat.com>
Date:   Wed Jul 9 10:36:23 2014 +0530

    Fix Wundef warning for __cplusplus
    
    All current uses of the __cplusplus macro only check if it is defined
    or not.  Fix this #if to use $ifdef like the rest of the code.

diff --git a/sysdeps/generic/unwind-pe.h b/sysdeps/generic/unwind-pe.h
index 3985fec998a2083d..b190cb34a102f5f9 100644
--- a/sysdeps/generic/unwind-pe.h
+++ b/sysdeps/generic/unwind-pe.h
@@ -22,7 +22,7 @@
    than duplicating code, however.  */
 
 /* If using C++, references to abort have to be qualified with std::.  */
-#if __cplusplus
+#ifdef __cplusplus
 #define __gxx_abort std::abort
 #else
 #define __gxx_abort abort