avoid some issues with c++ and X11

include/tradstdc.h

@@ -465,6 +465,7 @@ typedef genericptr genericptr_t; /* (void *) or (char *) */
  * function will cause a link failure on non-Unix platforms,
  * so it is preferrable to catch it early, during compile.
  */
+#if !defined(X11_BUILD) && !defined(__cplusplus)
 #if defined(__GNUC__) && !defined(__CLANG__)
 #if __GNUC__ >= 12
 extern char *index(const char *s, int c) __attribute__ ((unavailable));
@@ -477,6 +478,7 @@ extern char *index(const char *s, int c) __attribute__ ((unavailable));
 extern char *rindex(const char *s, int c) __attribute__ ((unavailable));
 #endif
 #endif
+#endif
 
 
 #endif /* TRADSTDC_H */

win/X11/dialogs.c

@@ -77,7 +77,9 @@
 #undef PRESERVE_NO_SYSV
 #endif
 
+#define X11_BUILD
 #include "config.h" /* #define for const for non __STDC__ compilers */
+#undef X11_BUILD
 #include "lint.h"   /* for nethack's nhStr() macro */
 #include "winX.h"   /* to make sure protoypes match corresponding functions */
 

win/X11/winX.c

@@ -16,6 +16,8 @@
 #define SHORT_FILENAMES
 #endif
 
+#define X11_BUILD
+
 #include <X11/Intrinsic.h>
 #include <X11/StringDefs.h>
 #include <X11/Shell.h>

win/X11/winmenu.c

@@ -33,6 +33,8 @@
 #undef PRESERVE_NO_SYSV
 #endif
 
+#define X11_BUILD
+
 #include "hack.h"
 #include "winX.h"
 

win/X11/winmisc.c

@@ -34,6 +34,8 @@
 #undef PRESERVE_NO_SYSV
 #endif
 
+#define X11_BUILD
+
 #include "hack.h"
 #include "func_tab.h"
 #include "winX.h"

win/X11/wintext.c

@@ -28,6 +28,8 @@
 #undef PRESERVE_NO_SYSV
 #endif
 
+#define X11_BUILD
+
 #include "hack.h"
 #include "winX.h"
 #include "xwindow.h"