--- apron/ap_config.h	2009-09-11 11:00:27.000000000 -0700
+++ apron/ap_config.h	2018-12-10 20:40:51.914905968 -0800
@@ -23,17 +23,6 @@
 static const bool true  = 1;
 #endif
 
-#if !(defined __USE_SVID || defined __USE_BSD || defined __USE_XOPEN_EXTENDED || defined __APPLE__ || defined __CYGWIN__)
-
-static inline char* strdup(const char* s){
-  char* s2;
-
-  s2 = malloc(strlen(s)+1);
-  strcpy(s2,s);
-  return s2;
-}
-#endif
-
 #ifdef __cplusplus
 }
 #endif