Index: generic/nsf.h
===================================================================
diff -u -ra422e30cf3600a498fac637e16604693577f7802 -r65d1c0f8d783d97a78b93f14871045fa9d4e5a41
--- generic/nsf.h	(.../nsf.h)	(revision a422e30cf3600a498fac637e16604693577f7802)
+++ generic/nsf.h	(.../nsf.h)	(revision 65d1c0f8d783d97a78b93f14871045fa9d4e5a41)
@@ -35,8 +35,8 @@
  * DEALINGS IN THE SOFTWARE.
  * */
 
-#ifndef _nsf_h_
-#define _nsf_h_
+#ifndef NSF_INCLUDED_nsf_h_
+#define NSF_INCLUDED_nsf_h_
 
 #include "tcl.h"
 
@@ -366,27 +366,26 @@
 #define NSF_ARG_SUBST_DEFAULT_BACKSLASHES 0x40000000u
 #define NSF_ARG_SUBST_DEFAULT_ALL         0x70000000u
 
-#undef  __GNUC_PREREQ
 #if defined __GNUC__ && defined __GNUC_MINOR__
-# define __GNUC_PREREQ(maj, min) \
+# define NSF__GNUC_PREREQ(maj, min) \
 	((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
 #else
-# define __GNUC_PREREQ(maj, min) (0)
+# define NSF__GNUC_PREREQ(maj, min) (0)
 #endif
 
-#if __GNUC_PREREQ(3, 3)
+#if NSF__GNUC_PREREQ(3, 3)
 # define NSF_nonnull(ARGS) __attribute__((__nonnull__(ARGS)))
 #else
 # define NSF_nonnull(ARGS)
 #endif
 
-#if __GNUC_PREREQ(6, 0)
+#if NSF__GNUC_PREREQ(6, 0)
 # define NSF_nonnull_assert(assertion)
 #else
 # define NSF_nonnull_assert(assertion) assert((assertion))
 #endif
 
-#if __GNUC_PREREQ(2, 96)
+#if NSF__GNUC_PREREQ(2, 96)
 # define NSF_pure __attribute__((pure))
 #else
 # define NSF_pure
@@ -397,13 +396,13 @@
  * Unfortunately, we can't combine NSF_attribute_format() with
  * functions called via stubs.
  */
-#if __GNUC_PREREQ(3, 4)
+#if NSF__GNUC_PREREQ(3, 4)
 # define NSF_attribute_format(ARGS) __attribute__((__format__ ARGS))
 #else
 # define NSF_attribute_format(ARGS)
 #endif
 
-#if __GNUC_PREREQ(7, 0)
+#if NSF__GNUC_PREREQ(7, 0)
 # define NSF_FALL_THROUGH __attribute__((fallthrough))
 #else
 # define NSF_FALL_THROUGH ((void)0)
@@ -533,4 +532,4 @@
 #define TCL_STORAGE_CLASS DLLIMPORT
 */
 
-#endif /* _nsf_h_ */
+#endif /* NSF_INCLUDED_nsf_h_ */
Index: generic/nsfInt.h
===================================================================
diff -u -ra422e30cf3600a498fac637e16604693577f7802 -r65d1c0f8d783d97a78b93f14871045fa9d4e5a41
--- generic/nsfInt.h	(.../nsfInt.h)	(revision a422e30cf3600a498fac637e16604693577f7802)
+++ generic/nsfInt.h	(.../nsfInt.h)	(revision 65d1c0f8d783d97a78b93f14871045fa9d4e5a41)
@@ -43,8 +43,8 @@
  *
  */
 
-#ifndef _nsf_int_h_
-#define _nsf_int_h_
+#ifndef NSF_INCLUDE_nsf_int_h_
+#define NSF_INCLUDE_nsf_int_h_
 
 /*
  * Well behaved compiler with C99 support should define __STDC_VERSION__
@@ -144,7 +144,7 @@
 # include <tclCompile.h>
 #endif
 
-#if __GNUC_PREREQ(2, 95)
+#if NSF__GNUC_PREREQ(2, 95)
 /* Use gcc branch prediction hint to minimize cost of e.g. DTrace
  * ENABLED checks.
  */
@@ -155,13 +155,13 @@
 #  define likely(x) (x)
 #endif
 
-#if __GNUC_PREREQ(3, 3)
+#if NSF__GNUC_PREREQ(3, 3)
 # define nonnull(ARGS) __attribute__((__nonnull__(ARGS)))
 #else
 # define nonnull(ARGS)
 #endif
 
-#if __GNUC_PREREQ(4, 9)
+#if NSF__GNUC_PREREQ(4, 9)
 # define returns_nonnull __attribute__((returns_nonnull))
 #else
 # define returns_nonnull
@@ -174,7 +174,7 @@
  * attribute could not be used, if declared as unused.
  */
 #ifdef UNUSED
-#elif __GNUC_PREREQ(2, 7)
+#elif NSF__GNUC_PREREQ(2, 7)
 # define UNUSED(x) UNUSED_ ## x __attribute__((unused))
 #elif defined(__LCLINT__)
 # define UNUSED(x) /*@unused@*/ (x)
@@ -1393,4 +1393,4 @@
   NsfCallStackFindCallingContext((interp), (offset), (framePtrPtr), NULL)
 
 EXTERN const char *Nsf_Configureoption[];
-#endif /* _nsf_int_h_ */
+#endif /* NSF_INCLUDE_nsf_int_h_ */
Index: generic/stubs8.5/nsfDecls.h
===================================================================
diff -u -ra963e8896fd07c345ccfa034cbd043344edbf083 -r65d1c0f8d783d97a78b93f14871045fa9d4e5a41
--- generic/stubs8.5/nsfDecls.h	(.../nsfDecls.h)	(revision a963e8896fd07c345ccfa034cbd043344edbf083)
+++ generic/stubs8.5/nsfDecls.h	(.../nsfDecls.h)	(revision 65d1c0f8d783d97a78b93f14871045fa9d4e5a41)
@@ -42,8 +42,8 @@
  *
  */
 
-#ifndef _NSFDECLS
-#define _NSFDECLS
+#ifndef NSF_INCLUDE_NSFDECLS
+#define NSF_INCLUDE_NSFDECLS
 
 /*
  * WARNING: This file is automatically generated by the tools/genStubs.tcl
@@ -569,5 +569,5 @@
 
 /* !END!: Do not edit above this line. */
 
-#endif /* _NSFDECLS */
+#endif /* NSF_INCLUDE_NSFDECLS */
 
Index: generic/stubs8.5/nsfIntDecls.h
===================================================================
diff -u -ra963e8896fd07c345ccfa034cbd043344edbf083 -r65d1c0f8d783d97a78b93f14871045fa9d4e5a41
--- generic/stubs8.5/nsfIntDecls.h	(.../nsfIntDecls.h)	(revision a963e8896fd07c345ccfa034cbd043344edbf083)
+++ generic/stubs8.5/nsfIntDecls.h	(.../nsfIntDecls.h)	(revision 65d1c0f8d783d97a78b93f14871045fa9d4e5a41)
@@ -43,8 +43,8 @@
  *
  */
 
-#ifndef _NSFINTDECLS
-#define _NSFINTDECLS
+#ifndef NSF_INCLUDE_NSFINTDECLS
+#define NSF_INCLUDE_NSFINTDECLS
 
 /*
  * WARNING: This file is automatically generated by the tools/genStubs.tcl
@@ -86,4 +86,4 @@
 
 /* !END!: Do not edit above this line. */
 
-#endif /* _NSFINTDECLS */
+#endif /* NSF_INCLUDE_NSFINTDECLS */
Index: generic/stubs8.6/nsfDecls.h
===================================================================
diff -u -ra963e8896fd07c345ccfa034cbd043344edbf083 -r65d1c0f8d783d97a78b93f14871045fa9d4e5a41
--- generic/stubs8.6/nsfDecls.h	(.../nsfDecls.h)	(revision a963e8896fd07c345ccfa034cbd043344edbf083)
+++ generic/stubs8.6/nsfDecls.h	(.../nsfDecls.h)	(revision 65d1c0f8d783d97a78b93f14871045fa9d4e5a41)
@@ -42,8 +42,8 @@
  *
  */
 
-#ifndef _NSFDECLS
-#define _NSFDECLS
+#ifndef NSF_INCLUDED_NSFDECLS
+#define NSF_INCLUDED_NSFDECLS
 
 /*
  * WARNING: This file is automatically generated by the tools/genStubs.tcl
@@ -364,5 +364,5 @@
 
 /* !END!: Do not edit above this line. */
 
-#endif /* _NSFDECLS */
+#endif /* NSF_INCLUDED_NSFDECLS */
 
Index: generic/stubs8.6/nsfIntDecls.h
===================================================================
diff -u -ra963e8896fd07c345ccfa034cbd043344edbf083 -r65d1c0f8d783d97a78b93f14871045fa9d4e5a41
--- generic/stubs8.6/nsfIntDecls.h	(.../nsfIntDecls.h)	(revision a963e8896fd07c345ccfa034cbd043344edbf083)
+++ generic/stubs8.6/nsfIntDecls.h	(.../nsfIntDecls.h)	(revision 65d1c0f8d783d97a78b93f14871045fa9d4e5a41)
@@ -43,8 +43,8 @@
  *
  */
 
-#ifndef _NSFINTDECLS
-#define _NSFINTDECLS
+#ifndef NSF_INCLUDED_NSFINTDECLS
+#define NSF_INCLUDED_NSFINTDECLS
 
 /*
  * WARNING: This file is automatically generated by the tools/genStubs.tcl
@@ -86,4 +86,4 @@
 
 /* !END!: Do not edit above this line. */
 
-#endif /* _NSFINTDECLS */
+#endif /* NSF_INCLUDED_NSFINTDECLS */
Index: generic/stubs8.7/nsfDecls.h
===================================================================
diff -u -ra963e8896fd07c345ccfa034cbd043344edbf083 -r65d1c0f8d783d97a78b93f14871045fa9d4e5a41
--- generic/stubs8.7/nsfDecls.h	(.../nsfDecls.h)	(revision a963e8896fd07c345ccfa034cbd043344edbf083)
+++ generic/stubs8.7/nsfDecls.h	(.../nsfDecls.h)	(revision 65d1c0f8d783d97a78b93f14871045fa9d4e5a41)
@@ -42,8 +42,8 @@
  *
  */
 
-#ifndef _NSFDECLS
-#define _NSFDECLS
+#ifndef NSF_INCLUDED_NSFDECLS
+#define NSF_INCLUDED_NSFDECLS
 
 /*
  * WARNING: This file is automatically generated by the tools/genStubs.tcl
@@ -364,5 +364,5 @@
 
 /* !END!: Do not edit above this line. */
 
-#endif /* _NSFDECLS */
+#endif /* NSF_INCLUDED_NSFDECLS */
 
Index: generic/stubs8.7/nsfIntDecls.h
===================================================================
diff -u -ra963e8896fd07c345ccfa034cbd043344edbf083 -r65d1c0f8d783d97a78b93f14871045fa9d4e5a41
--- generic/stubs8.7/nsfIntDecls.h	(.../nsfIntDecls.h)	(revision a963e8896fd07c345ccfa034cbd043344edbf083)
+++ generic/stubs8.7/nsfIntDecls.h	(.../nsfIntDecls.h)	(revision 65d1c0f8d783d97a78b93f14871045fa9d4e5a41)
@@ -43,8 +43,8 @@
  *
  */
 
-#ifndef _NSFINTDECLS
-#define _NSFINTDECLS
+#ifndef NSF_INCLUDED_NSFINTDECLS
+#define NSF_INCLUDED_NSFINTDECLS
 
 /*
  * WARNING: This file is automatically generated by the tools/genStubs.tcl
@@ -86,4 +86,4 @@
 
 /* !END!: Do not edit above this line. */
 
-#endif /* _NSFINTDECLS */
+#endif /* NSF_INCLUDED_NSFINTDECLS */