--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,16 @@
+2007-01-28  Paul Eggert  <eggert@cs.ucla.edu>
+
+	* lib/regex.h (_Restrict_): Renamed from __restrict, to avoid
+	a circularity problem with HP-UX ia64 reported by Bob Proulx in
+	<http://lists.gnu.org/archive/html/bug-gnulib/2007-01/msg00394.html>.
+	All uses changed.
+	(_Restrict_arr_): Renamed from __restrict_arr, for similar reasons.
+	All uses changed.
+	* lib/regcomp.c, lib/regexec.c: Change all uses from __restrict
+	to _Restrict_.
+	* lib/regexec.c (regexec): Declare pmatch with _Restrict_arr_, so that
+	the parameter matches the prototype.
+
 2007-01-28  Jim Meyering  <jim@meyering.net>
 
 	* modules/sys_time (Makefile.am) [MOSTLYCLEANFILES]: Do use

--- a/lib/regcomp.c
+++ b/lib/regcomp.c
@@ -451,8 +451,8 @@
 
 int
 regcomp (preg, pattern, cflags)
-    regex_t *__restrict preg;
-    const char *__restrict pattern;
+    regex_t *_Restrict_ preg;
+    const char *_Restrict_ pattern;
     int cflags;
 {
   reg_errcode_t ret;
@@ -515,13 +515,13 @@
 size_t
 regerror (errcode, preg, errbuf, errbuf_size)
     int errcode;
-    const regex_t *__restrict preg;
-    char *__restrict errbuf;
+    const regex_t *_Restrict_ preg;
+    char *_Restrict_ errbuf;
     size_t errbuf_size;
 #else /* size_t might promote */
 size_t
-regerror (int errcode, const regex_t *__restrict preg,
-	  char *__restrict errbuf, size_t errbuf_size)
+regerror (int errcode, const regex_t *_Restrict_ preg,
+	  char *_Restrict_ errbuf, size_t errbuf_size)
 #endif
 {
   const char *msg;

--- a/lib/regex.h
+++ b/lib/regex.h
@@ -625,41 +625,45 @@
 #endif
 
 /* GCC 2.95 and later have "__restrict"; C99 compilers have
-   "restrict", and "configure" may have defined "restrict".  */
-#ifndef __restrict
-# if ! (2 < __GNUC__ || (2 == __GNUC__ && 95 <= __GNUC_MINOR__))
-#  if defined restrict || 199901L <= __STDC_VERSION__
-#   define __restrict restrict
-#  else
-#   define __restrict
-#  endif
+   "restrict", and "configure" may have defined "restrict".
+   Other compilers use __restrict, __restrict__, and _Restrict, and
+   'configure' might #define 'restrict' to those words, so pick a
+   different name.  */
+#ifndef _Restrict_
+# if 199901L <= __STDC_VERSION__
+#  define _Restrict_ restrict
+# elif 2 < __GNUC__ || (2 == __GNUC__ && 95 <= __GNUC_MINOR__)
+#  define _Restrict_ __restrict
+# else
+#  define _Restrict_
 # endif
 #endif
 /* gcc 3.1 and up support the [restrict] syntax.  Don't trust
    sys/cdefs.h's definition of __restrict_arr, though, as it
    mishandles gcc -ansi -pedantic.  */
-#undef __restrict_arr
-#if ((199901L <= __STDC_VERSION__					\
-      || ((3 < __GNUC__ || (3 == __GNUC__ && 1 <= __GNUC_MINOR__))	\
-	  && !__STRICT_ANSI__))						\
-     && !defined __GNUG__)
-# define __restrict_arr __restrict
-#else
-# define __restrict_arr
+#ifndef _Restrict_arr_
+# if ((199901L <= __STDC_VERSION__					\
+       || ((3 < __GNUC__ || (3 == __GNUC__ && 1 <= __GNUC_MINOR__))	\
+	   && !__STRICT_ANSI__))					\
+      && !defined __GNUG__)
+#  define _Restrict_arr_ _Restrict_
+# else
+#  define _Restrict_arr_
+# endif
 #endif
 
 /* POSIX compatibility.  */
-extern int regcomp (regex_t *__restrict __preg,
-		    const char *__restrict __pattern,
+extern int regcomp (regex_t *_Restrict_ __preg,
+		    const char *_Restrict_ __pattern,
 		    int __cflags);
 
-extern int regexec (const regex_t *__restrict __preg,
-		    const char *__restrict __string, size_t __nmatch,
-		    regmatch_t __pmatch[__restrict_arr],
+extern int regexec (const regex_t *_Restrict_ __preg,
+		    const char *_Restrict_ __string, size_t __nmatch,
+		    regmatch_t __pmatch[_Restrict_arr_],
 		    int __eflags);
 
-extern size_t regerror (int __errcode, const regex_t *__restrict __preg,
-			char *__restrict __errbuf, size_t __errbuf_size);
+extern size_t regerror (int __errcode, const regex_t *_Restrict_ __preg,
+			char *_Restrict_ __errbuf, size_t __errbuf_size);
 
 extern void regfree (regex_t *__preg);
 

--- a/lib/regexec.c
+++ b/lib/regexec.c
@@ -221,10 +221,10 @@
 
 int
 regexec (preg, string, nmatch, pmatch, eflags)
-    const regex_t *__restrict preg;
-    const char *__restrict string;
+    const regex_t *_Restrict_ preg;
+    const char *_Restrict_ string;
     size_t nmatch;
-    regmatch_t pmatch[];
+    regmatch_t pmatch[_Restrict_arr_];
     int eflags;
 {
   reg_errcode_t err;
@@ -267,8 +267,8 @@
 
 int
 attribute_compat_text_section
-__compat_regexec (const regex_t *__restrict preg,
-		  const char *__restrict string, size_t nmatch,
+__compat_regexec (const regex_t *_Restrict_ preg,
+		  const char *_Restrict_ string, size_t nmatch,
 		  regmatch_t pmatch[], int eflags)
 {
   return regexec (preg, string, nmatch, pmatch,