diff --git a/include/features.h b/include/features.h
index 2e16874792..a34e26f52c 100644
--- a/include/features.h
+++ b/include/features.h
@@ -277,6 +277,14 @@
 #define __GLIBC_PREREQ(maj, min) \
 	((__GLIBC__ << 16) + __GLIBC_MINOR__ >= ((maj) << 16) + (min))
 
+/* Decide whether a compiler supports the long long datatypes.  */
+#if defined __GNUC__ \
+    || (defined __PGI && defined __i386__ ) \
+    || (defined __INTEL_COMPILER && (defined __i386__ || defined __ia64__)) \
+    || (defined __STDC_VERSION && __STDC_VERSION >= 199901L)
+# define __GLIBC_HAVE_LONG_LONG	1
+#endif
+
 /* This is here only because every header file already includes this one.  */
 #ifndef __ASSEMBLER__
 # ifndef _SYS_CDEFS_H
diff --git a/posix/sys/types.h b/posix/sys/types.h
index cd114876fe..6895c0dec0 100644
--- a/posix/sys/types.h
+++ b/posix/sys/types.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1991,92,94,95,96,97,98,99,2000 Free Software Foundation, Inc.
+/* Copyright (C) 1991,92,94,95,96,97,98,99,2000,2001 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -162,7 +162,7 @@ typedef unsigned int uint;
 typedef	char int8_t;
 typedef	short int int16_t;
 typedef	int int32_t;
-#  ifdef __GNUC__
+#  if __GLIBC_HAVE_LONG_LONG
 __extension__ typedef long long int int64_t;
 #  endif
 # endif
@@ -171,7 +171,7 @@ __extension__ typedef long long int int64_t;
 typedef	unsigned char u_int8_t;
 typedef	unsigned short int u_int16_t;
 typedef	unsigned int u_int32_t;
-# ifdef __GNUC__
+# if __GLIBC_HAVE_LONG_LONG
 __extension__ typedef unsigned long long int u_int64_t;
 # endif
 
diff --git a/stdlib/stdlib.h b/stdlib/stdlib.h
index 74082c485d..9b0ed9e3a6 100644
--- a/stdlib/stdlib.h
+++ b/stdlib/stdlib.h
@@ -140,7 +140,7 @@ extern int atoi (__const char *__nptr) __THROW __attribute_pure__;
 /* Convert a string to a long integer.  */
 extern long int atol (__const char *__nptr) __THROW __attribute_pure__;
 
-#if defined __USE_ISOC99 || (defined __GNUC__ && defined __USE_MISC)
+#if defined __USE_ISOC99 || (defined __GLIBC_HAVE_LONG_LONG && defined __USE_MISC)
 /* Convert a string to a long long integer.  */
 __extension__ extern long long int atoll (__const char *__nptr)
      __THROW __attribute_pure__;
@@ -167,7 +167,7 @@ extern unsigned long int strtoul (__const char *__restrict __nptr,
 				  char **__restrict __endptr, int __base)
      __THROW;
 
-#if defined __GNUC__ && defined __USE_BSD
+#if defined __GLIBC_HAVE_LONG_LONG && defined __USE_BSD
 /* Convert a string to a quadword integer.  */
 __extension__
 extern long long int strtoq (__const char *__restrict __nptr,
@@ -179,7 +179,7 @@ extern unsigned long long int strtouq (__const char *__restrict __nptr,
      __THROW;
 #endif /* GCC and use BSD.  */
 
-#if defined __USE_ISOC99 || (defined __GNUC__ && defined __USE_MISC)
+#if defined __USE_ISOC99 || (defined __GLIBC_HAVE_LONG_LONG && defined __USE_MISC)
 /* These functions will part of the standard C library in ISO C99.  */
 
 /* Convert a string to a quadword integer.  */
diff --git a/sysdeps/unix/sysv/linux/bits/types.h b/sysdeps/unix/sysv/linux/bits/types.h
index bdda9388ac..ffc346fc75 100644
--- a/sysdeps/unix/sysv/linux/bits/types.h
+++ b/sysdeps/unix/sysv/linux/bits/types.h
@@ -33,7 +33,7 @@ typedef unsigned char __u_char;
 typedef unsigned short __u_short;
 typedef unsigned int __u_int;
 typedef unsigned long __u_long;
-#ifdef __GNUC__
+#ifdef __GLIBC_HAVE_LONG_LONG
 __extension__ typedef unsigned long long int __u_quad_t;
 __extension__ typedef long long int __quad_t;
 #else
@@ -52,7 +52,7 @@ typedef signed short int __int16_t;
 typedef unsigned short int __uint16_t;
 typedef signed int __int32_t;
 typedef unsigned int __uint32_t;
-#ifdef __GNUC__
+#ifdef __GLIBC_HAVE_LONG_LONG
 __extension__ typedef signed long long int __int64_t;
 __extension__ typedef unsigned long long int __uint64_t;
 #endif
@@ -63,7 +63,7 @@ typedef __u_int __uid_t;		/* Type of user identifications.  */
 typedef __u_int __gid_t;		/* Type of group identifications.  */
 typedef __u_long __ino_t;		/* Type of file serial numbers.  */
 typedef __u_int __mode_t;		/* Type of file attribute bitmasks.  */
-typedef __u_int __nlink_t; 		/* Type of file link counts.  */
+typedef __u_int __nlink_t;		/* Type of file link counts.  */
 typedef long int __off_t;		/* Type of file sizes and offsets.  */
 typedef __quad_t __loff_t;		/* Type of file sizes and offsets.  */
 typedef int __pid_t;			/* Type of process identifications.  */