1.0.10.18: Define __USE_GNU only if it wasn't already defined.

[sbcl.git] / src / runtime / backtrace.c

diff --git a/src/runtime/backtrace.c b/src/runtime/backtrace.c
index e7420e9..98189b9 100644 (file)
--- a/src/runtime/backtrace.c
+++ b/src/runtime/backtrace.c
@@ -34,9 +34,11 @@
 #include "thread.h"
 
 #ifdef LISP_FEATURE_OS_PROVIDES_DLADDR
+# ifndef __USE_GNU
 /* __USE_GNU needed if we want dladdr() and Dl_Info from glibc. */
-#define __USE_GNU
-#include "dlfcn.h"
+# define __USE_GNU
+# endif
+# include "dlfcn.h"
 #endif
 
 #if !(defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64))