diff --git a/include/GL/glext.h b/include/GL/glext.h
index 2b22714c305..f7377bb3103 100644
--- a/include/GL/glext.h
+++ b/include/GL/glext.h
@@ -3419,16 +3419,16 @@ typedef unsigned short GLhalfNV;
 #endif
 
 #ifndef GLEXT_64_TYPES_DEFINED
-/* This code block is duplicated in glext.h, so must be protected */
+/* This code block is duplicated in glxext.h, so must be protected */
 #define GLEXT_64_TYPES_DEFINED
 /* Define int32_t, int64_t, and uint64_t types for UST/MSC */
 /* (as used in the GL_EXT_timer_query extension). */
 #if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
 #include <inttypes.h>
-#elif defined(__sun__)
+#elif defined(__sun__) || defined(__digital__)
 #include <inttypes.h>
 #if defined(__STDC__)
-#if defined(__arch64__)
+#if defined(__arch64__) || defined(_LP64)
 typedef long int int64_t;
 typedef unsigned long int uint64_t;
 #else
@@ -3436,7 +3436,7 @@ typedef long long int int64_t;
 typedef unsigned long long int uint64_t;
 #endif /* __arch64__ */
 #endif /* __STDC__ */
-#elif defined( __VMS )
+#elif defined( __VMS ) || defined(__sgi)
 #include <inttypes.h>
 #elif defined(__SCO__) || defined(__USLC__)
 #include <stdint.h>
diff --git a/include/GL/glxext.h b/include/GL/glxext.h
index 0f66df6277a..aedc311cbf4 100644
--- a/include/GL/glxext.h
+++ b/include/GL/glxext.h
@@ -380,7 +380,7 @@ typedef struct {
 #endif
 
 #ifndef GLEXT_64_TYPES_DEFINED
-/* This code block is duplicated in glxext.h, so must be protected */
+/* This code block is duplicated in glext.h, so must be protected */
 #define GLEXT_64_TYPES_DEFINED
 /* Define int32_t, int64_t, and uint64_t types for UST/MSC */
 /* (as used in the GLX_OML_sync_control extension). */
@@ -389,7 +389,7 @@ typedef struct {
 #elif defined(__sun__) || defined(__digital__)
 #include <inttypes.h>
 #if defined(__STDC__)
-#if defined(__arch64__)
+#if defined(__arch64__) || defined(_LP64)
 typedef long int int64_t;
 typedef unsigned long int uint64_t;
 #else
@@ -397,7 +397,7 @@ typedef long long int int64_t;
 typedef unsigned long long int uint64_t;
 #endif /* __arch64__ */
 #endif /* __STDC__ */
-#elif defined( __VMS )
+#elif defined( __VMS ) || defined(__sgi)
 #include <inttypes.h>
 #elif defined(__SCO__) || defined(__USLC__)
 #include <stdint.h>