diff --git a/nsprpub/configure b/nsprpub/configure
index a2704ef306c..9f376868db7 100755
--- a/nsprpub/configure
+++ b/nsprpub/configure
@@ -4147,19 +4147,30 @@ EOF
 #define _REENTRANT 1
 EOF
 
-    ac_safe=`echo "machine/builtins.h" | sed 'y%./+-%__p_%'`
+
+    if echo "$OS_RELEASE" | egrep -c '(V2.0|V3.2)' 2>/dev/null ; then
+        USE_NSPR_THREADS=1
+    fi
+
+    if test -z "$GNU_CC"; then
+        CC="$CC -std1 -ieee_with_inexact"
+        if test "$OS_RELEASE" != "V2.0"; then
+            CC="$CC -readonly_strings"
+        fi
+        _OPTIMIZE_FLAGS="$_OPTIMIZE_FLAGS -Olimit 4000"
+        ac_safe=`echo "machine/builtins.h" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for machine/builtins.h""... $ac_c" 1>&6
-echo "configure:4153: checking for machine/builtins.h" >&5
+echo "configure:4164: checking for machine/builtins.h" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 4158 "configure"
+#line 4169 "configure"
 #include "confdefs.h"
 #include <machine/builtins.h>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:4163: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:4174: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -4183,17 +4194,6 @@ else
   echo "$ac_t""no" 1>&6
 fi
 
-
-    if echo "$OS_RELEASE" | egrep -c '(V2.0|V3.2)' 2>/dev/null ; then
-        USE_NSPR_THREADS=1
-    fi
-
-    if test -z "$GNU_CC"; then
-        CC="$CC -std1 -ieee_with_inexact"
-        if test "$OS_RELEASE" != "V2.0"; then
-            CC="$CC -readonly_strings"
-        fi
-        _OPTIMIZE_FLAGS="$_OPTIMIZE_FLAGS -Olimit 4000"
     fi
 
     if echo $OS_RELEASE | egrep -c '(V2.0|V3.2)' 2>/dev/null; then
diff --git a/nsprpub/configure.in b/nsprpub/configure.in
index 8fb25e5ee73..bea07abccc0 100644
--- a/nsprpub/configure.in
+++ b/nsprpub/configure.in
@@ -1454,7 +1454,6 @@ mips-sony-newsos*)
     AC_DEFINE(XP_UNIX)
     AC_DEFINE(OSF1)
     AC_DEFINE(_REENTRANT)
-    AC_CHECK_HEADER(machine/builtins.h, AC_DEFINE(OSF1_HAVE_MACHINE_BUILTINS_H))
 
     if echo "$OS_RELEASE" | egrep -c '(V2.0|V3.2)' 2>/dev/null ; then
         USE_NSPR_THREADS=1
@@ -1466,6 +1465,7 @@ mips-sony-newsos*)
             CC="$CC -readonly_strings"
         fi
         _OPTIMIZE_FLAGS="$_OPTIMIZE_FLAGS -Olimit 4000"
+        AC_CHECK_HEADER(machine/builtins.h, AC_DEFINE(OSF1_HAVE_MACHINE_BUILTINS_H))
     fi
 
     if echo $OS_RELEASE | egrep -c '(V2.0|V3.2)' 2>/dev/null; then
diff --git a/nsprpub/pr/src/md/unix/unix.c b/nsprpub/pr/src/md/unix/unix.c
index 42a0f1e83c0..704fa11ace0 100644
--- a/nsprpub/pr/src/md/unix/unix.c
+++ b/nsprpub/pr/src/md/unix/unix.c
@@ -2727,6 +2727,28 @@ static void* _MD_Unix_mmap64(
 }  /* _MD_Unix_mmap64 */
 #endif /* defined(_PR_NO_LARGE_FILES) || defined(SOLARIS2_5) */
 
+#if defined(OSF1) && defined(__GNUC__)
+
+/*
+ * On OSF1 V5.0A, <sys/stat.h> defines stat and fstat as
+ * macros when compiled under gcc, so it is rather tricky to
+ * take the addresses of the real functions the macros expend
+ * to.  A simple solution is to define forwarder functions
+ * and take the addresses of the forwarder functions instead.
+ */
+
+static int stat_forwarder(const char *path, struct stat *buffer)
+{
+    return stat(path, buffer);
+}
+
+static int fstat_forwarder(int filedes, struct stat *buffer)
+{
+    return fstat(filedes, buffer);
+}
+
+#endif
+
 static void _PR_InitIOV(void)
 {
 #if defined(SOLARIS2_5)
@@ -2771,8 +2793,13 @@ static void _PR_InitIOV(void)
 #elif defined(_PR_HAVE_LARGE_OFF_T)
     _md_iovector._open64 = open;
     _md_iovector._mmap64 = mmap;
+#if defined(OSF1) && defined(__GNUC__)
+    _md_iovector._fstat64 = fstat_forwarder;
+    _md_iovector._stat64 = stat_forwarder;
+#else
     _md_iovector._fstat64 = fstat;
     _md_iovector._stat64 = stat;
+#endif
     _md_iovector._lseek64 = lseek;
 #else
 #error "I don't know yet"
diff --git a/nsprpub/pr/src/md/unix/uxrng.c b/nsprpub/pr/src/md/unix/uxrng.c
index 5cfeeefdcc7..6add3bf17de 100644
--- a/nsprpub/pr/src/md/unix/uxrng.c
+++ b/nsprpub/pr/src/md/unix/uxrng.c
@@ -101,7 +101,11 @@ GetHighResClock(void *buf, size_t maxbytes)
 {
     unsigned long t;
 
+#ifdef __GNUC__
+    __asm__("rpcc %0" : "=r" (t));
+#else
     t = asm("rpcc %v0");
+#endif
     return _pr_CopyLowBits(buf, maxbytes, &t, sizeof(t));
 }