* Makefile.in (CFILES): Add lrealpath.c.

	(REQUIRED_OFILES): Add lrealpath.o.
	(lrealpath.o): Add rule.
	* aclocal.m4 (libiberty_NEED_DECLARATION): Add.
	* configure.in: Add realpath and canonicalize_file_name to
	checkfuncs and AC_CHECK_FUNCS.  Use libiberty_NEED_DECLARATION
	for canonicalize_file_name.
	* lrealpath.c: New file.
	* make-relative-prefix.c: Update documentation.
	(make_relative_prefix): Simplify.  Use lbasename and lrealpath.
	* config.in: Regenerated.
	* configure: Regenerated.
	* functions.texi: Regenerated.

9 files changed, 426 insertions, 121 deletions

diff --git a/libiberty/ChangeLog b/libiberty/ChangeLog
index 50bd29d..f470380 100644
--- a/libiberty/ChangeLog
+++ b/libiberty/ChangeLog
@@ -1,3 +1,19 @@
+2003-02-20  Daniel Jacobowitz  <drow@mvista.com>
+
+	* Makefile.in (CFILES): Add lrealpath.c.
+	(REQUIRED_OFILES): Add lrealpath.o.
+	(lrealpath.o): Add rule.
+	* aclocal.m4 (libiberty_NEED_DECLARATION): Add.
+	* configure.in: Add realpath and canonicalize_file_name to
+	checkfuncs and AC_CHECK_FUNCS.  Use libiberty_NEED_DECLARATION
+	for canonicalize_file_name.
+	* lrealpath.c: New file.
+	* make-relative-prefix.c: Update documentation.
+	(make_relative_prefix): Simplify.  Use lbasename and lrealpath.
+	* config.in: Regenerated.
+	* configure: Regenerated.
+	* functions.texi: Regenerated.
+
 2003-02-20  jmc  <jmc@prioris.mini.pw.edu.pl>
 
 	* cplus_dem.c: Fix typo: intializes -> initializes.
diff --git a/libiberty/Makefile.in b/libiberty/Makefile.in
index 761c674..c576357 100644
--- a/libiberty/Makefile.in
+++ b/libiberty/Makefile.in
@@ -137,6 +137,7 @@ CFILES = alloca.c argv.c asprintf.c atexit.c				\
 	hashtab.c hex.c							\
 	index.c insque.c						\
 	lbasename.c							\
+	lrealpath.c							\
 	make-relative-prefix.c						\
 	make-temp-file.c md5.c memchr.c memcmp.c memcpy.c memmove.c	\
 	 memset.c mkstemps.c						\
@@ -165,6 +166,7 @@ REQUIRED_OFILES = regex.o cplus-dem.o cp-demangle.o md5.o		\
 	getopt.o getopt1.o getpwd.o getruntime.o			\
 	hashtab.o hex.o							\
 	lbasename.o							\
+	lrealpath.o							\
 	make-relative-prefix.o						\
 	make-temp-file.o						\
 	objalloc.o obstack.o						\
@@ -443,6 +445,7 @@ hashtab.o: config.h $(INCDIR)/ansidecl.h $(INCDIR)/hashtab.h \
 hex.o: $(INCDIR)/ansidecl.h $(INCDIR)/libiberty.h
 lbasename.o: $(INCDIR)/ansidecl.h $(INCDIR)/libiberty.h \
 	$(INCDIR)/safe-ctype.h
+lrealpath.o: config.h $(INCDIR)/ansidecl.h $(INCDIR)/libiberty.h
 make-relative-prefix.o: config.h $(INCDIR)/ansidecl.h $(INCDIR)/libiberty.h
 make-temp-file.o: config.h $(INCDIR)/ansidecl.h $(INCDIR)/libiberty.h
 md5.o: config.h $(INCDIR)/ansidecl.h $(INCDIR)/md5.h
diff --git a/libiberty/aclocal.m4 b/libiberty/aclocal.m4
index 103e246..6c5dc6a 100644
--- a/libiberty/aclocal.m4
+++ b/libiberty/aclocal.m4
@@ -87,6 +87,35 @@ then AC_DEFINE(NEED_DECLARATION_ERRNO, 1,
 fi
 ])
 
+dnl See whether we need a declaration for a function.
+AC_DEFUN(libiberty_NEED_DECLARATION,
+[AC_MSG_CHECKING([whether $1 must be declared])
+AC_CACHE_VAL(libiberty_cv_decl_needed_$1,
+[AC_TRY_COMPILE([
+#include "confdefs.h"
+#include <stdio.h>
+#ifdef HAVE_STRING_H
+#include <string.h>
+#else
+#ifdef HAVE_STRINGS_H
+#include <strings.h>
+#endif
+#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif],
+[char *(*pfn) = (char *(*)) $1],
+libiberty_cv_decl_needed_$1=no, libiberty_cv_decl_needed_$1=yes)])
+AC_MSG_RESULT($libiberty_cv_decl_needed_$1)
+if test $libiberty_cv_decl_needed_$1 = yes; then
+  AC_DEFINE([NEED_DECLARATION_]translit($1, [a-z], [A-Z]), 1,
+            [Define if $1 is not declared in system header files.])
+fi
+])dnl
+
 # FIXME: We temporarily define our own version of AC_PROG_CC.  This is
 # copied from autoconf 2.12, but does not call AC_PROG_CC_WORKS.  We
 # are probably using a cross compiler, which will not be able to fully
diff --git a/libiberty/config.in b/libiberty/config.in
index 43adcfd..738f075 100644
--- a/libiberty/config.in
+++ b/libiberty/config.in
@@ -1,4 +1,4 @@
-/* config.in.  Generated automatically from configure.in by autoheader.  */
+/* config.in.  Generated automatically from configure.in by autoheader 2.13.  */
 
 /* Define to empty if the keyword does not work.  */
 #undef const
@@ -63,6 +63,9 @@
 /* Define if you have the calloc function.  */
 #undef HAVE_CALLOC
 
+/* Define if you have the canonicalize_file_name function.  */
+#undef HAVE_CANONICALIZE_FILE_NAME
+
 /* Define if you have the clock function.  */
 #undef HAVE_CLOCK
 
@@ -117,6 +120,9 @@
 /* Define if you have the random function.  */
 #undef HAVE_RANDOM
 
+/* Define if you have the realpath function.  */
+#undef HAVE_REALPATH
+
 /* Define if you have the rename function.  */
 #undef HAVE_RENAME
 
@@ -258,3 +264,6 @@
         STACK_DIRECTION = 0 => direction of growth unknown */
 #undef STACK_DIRECTION
 
+/* Define if canonicalize_file_name is not declared in system header files. */
+#undef NEED_DECLARATION_CANONICALIZE_FILE_NAME
+
diff --git a/libiberty/configure b/libiberty/configure
index 6e754dd..320d854 100755
--- a/libiberty/configure
+++ b/libiberty/configure
@@ -1738,6 +1738,7 @@ funcs="$funcs waitpid"
 vars="sys_errlist sys_nerr sys_siglist"
 
 checkfuncs="getrusage on_exit psignal strerror strsignal sysconf times sbrk gettimeofday"
+checkfuncs="$checkfuncs realpath canonicalize_file_name"
 
 # These are neither executed nor required, but they help keep
 # autoheader happy without adding a bunch of text to acconfig.h.
@@ -1745,12 +1746,12 @@ if test "x" = "y"; then
   for ac_func in asprintf atexit basename bcmp bcopy bsearch bzero calloc clock
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:1749: checking for $ac_func" >&5
+echo "configure:1750: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1754 "configure"
+#line 1755 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -1773,7 +1774,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:1777: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1778: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -1800,12 +1801,12 @@ done
   for ac_func in getcwd getpagesize index insque mkstemps memchr memcmp memcpy
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:1804: checking for $ac_func" >&5
+echo "configure:1805: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1809 "configure"
+#line 1810 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -1828,7 +1829,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:1832: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1833: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -1855,12 +1856,12 @@ done
   for ac_func in memmove memset putenv random rename rindex sigsetmask
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:1859: checking for $ac_func" >&5
+echo "configure:1860: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1864 "configure"
+#line 1865 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -1883,7 +1884,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:1887: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1888: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -1910,12 +1911,12 @@ done
   for ac_func in strcasecmp setenv strchr strdup strncasecmp strrchr strstr
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:1914: checking for $ac_func" >&5
+echo "configure:1915: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1919 "configure"
+#line 1920 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -1938,7 +1939,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:1942: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1943: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -1965,12 +1966,12 @@ done
   for ac_func in strtod strtol strtoul tmpnam vasprintf vfprintf vprintf
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:1969: checking for $ac_func" >&5
+echo "configure:1970: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1974 "configure"
+#line 1975 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -1993,7 +1994,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:1997: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1998: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -2020,12 +2021,12 @@ done
   for ac_func in vsprintf waitpid getrusage on_exit psignal strerror strsignal
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:2024: checking for $ac_func" >&5
+echo "configure:2025: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2029 "configure"
+#line 2030 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2048,7 +2049,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2052: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2053: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -2075,12 +2076,12 @@ done
   for ac_func in sysconf times sbrk gettimeofday ffs
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:2079: checking for $ac_func" >&5
+echo "configure:2080: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2084 "configure"
+#line 2085 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2103,7 +2104,62 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2107: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2108: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+  rm -rf conftest*
+  eval "ac_cv_func_$ac_func=yes"
+else
+  echo "configure: failed program was:" >&5
+  cat conftest.$ac_ext >&5
+  rm -rf conftest*
+  eval "ac_cv_func_$ac_func=no"
+fi
+rm -f conftest*
+fi
+
+if eval "test \"`echo '$ac_cv_func_'$ac_func`\" = yes"; then
+  echo "$ac_t""yes" 1>&6
+    ac_tr_func=HAVE_`echo $ac_func | tr 'abcdefghijklmnopqrstuvwxyz' 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'`
+  cat >> confdefs.h <<EOF
+#define $ac_tr_func 1
+EOF
+ 
+else
+  echo "$ac_t""no" 1>&6
+fi
+done
+
+  for ac_func in realpath canonicalize_file_name
+do
+echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
+echo "configure:2135: checking for $ac_func" >&5
+if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
+  echo $ac_n "(cached) $ac_c" 1>&6
+else
+  cat > conftest.$ac_ext <<EOF
+#line 2140 "configure"
+#include "confdefs.h"
+/* System header to define __stub macros and hopefully few prototypes,
+    which can conflict with char $ac_func(); below.  */
+#include <assert.h>
+/* Override any gcc2 internal prototype to avoid an error.  */
+/* We use char because int might match the return type of a gcc2
+    builtin and then its argument prototype would still apply.  */
+char $ac_func();
+
+int main() {
+
+/* The GNU C library defines this for functions which it implements
+    to always fail with ENOSYS.  Some functions are actually named
+    something starting with __ and the normal name is an alias.  */
+#if defined (__stub_$ac_func) || defined (__stub___$ac_func)
+choke me
+#else
+$ac_func();
+#endif
+
+; return 0; }
+EOF
+if { (eval echo configure:2163: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -2333,7 +2389,7 @@ if test -z "${setobjs}"; then
   # We haven't set the list of objects yet.  Use the standard autoconf
   # tests.  This will only work if the compiler works.
   echo $ac_n "checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works""... $ac_c" 1>&6
-echo "configure:2337: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works" >&5
+echo "configure:2393: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works" >&5
 
 ac_ext=c
 # CFLAGS is not in ac_cpp because -g, -O, etc. are not valid cpp options.
@@ -2344,12 +2400,12 @@ cross_compiling=$ac_cv_prog_cc_cross
 
 cat > conftest.$ac_ext << EOF
 
-#line 2348 "configure"
+#line 2404 "configure"
 #include "confdefs.h"
 
 main(){return(0);}
 EOF
-if { (eval echo configure:2353: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2409: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   ac_cv_prog_cc_works=yes
   # If we can't run a trivial program, we are probably using a cross compiler.
   if (./conftest; exit) 2>/dev/null; then
@@ -2375,19 +2431,19 @@ if test $ac_cv_prog_cc_works = no; then
   { echo "configure: error: installation or configuration problem: C compiler cannot create executables." 1>&2; exit 1; }
 fi
 echo $ac_n "checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler""... $ac_c" 1>&6
-echo "configure:2379: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler" >&5
+echo "configure:2435: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler" >&5
 echo "$ac_t""$ac_cv_prog_cc_cross" 1>&6
 cross_compiling=$ac_cv_prog_cc_cross
 
   for ac_func in $funcs
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:2386: checking for $ac_func" >&5
+echo "configure:2442: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2391 "configure"
+#line 2447 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2410,7 +2466,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2414: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2470: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -2437,12 +2493,12 @@ done
 
 
   echo $ac_n "checking whether alloca needs Cray hooks""... $ac_c" 1>&6
-echo "configure:2441: checking whether alloca needs Cray hooks" >&5
+echo "configure:2497: checking whether alloca needs Cray hooks" >&5
 if eval "test \"`echo '$''{'ac_cv_os_cray'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2446 "configure"
+#line 2502 "configure"
 #include "confdefs.h"
 #if defined(CRAY) && ! defined(CRAY2)
 webecray
@@ -2467,12 +2523,12 @@ echo "$ac_t""$ac_cv_os_cray" 1>&6
 if test $ac_cv_os_cray = yes; then
   for ac_func in _getb67 GETB67 getb67; do
     echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:2471: checking for $ac_func" >&5
+echo "configure:2527: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2476 "configure"
+#line 2532 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2495,7 +2551,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2499: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2555: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -2521,7 +2577,7 @@ fi
 fi
 
 echo $ac_n "checking stack direction for C alloca""... $ac_c" 1>&6
-echo "configure:2525: checking stack direction for C alloca" >&5
+echo "configure:2581: checking stack direction for C alloca" >&5
 if eval "test \"`echo '$''{'ac_cv_c_stack_direction'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2529,7 +2585,7 @@ else
   ac_cv_c_stack_direction=0
 else
   cat > conftest.$ac_ext <<EOF
-#line 2533 "configure"
+#line 2589 "configure"
 #include "confdefs.h"
 find_stack_direction ()
 {
@@ -2548,7 +2604,7 @@ main ()
   exit (find_stack_direction() < 0);
 }
 EOF
-if { (eval echo configure:2552: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
+if { (eval echo configure:2608: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
 then
   ac_cv_c_stack_direction=1
 else
@@ -2570,17 +2626,17 @@ EOF
 
   ac_safe=`echo "vfork.h" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for vfork.h""... $ac_c" 1>&6
-echo "configure:2574: checking for vfork.h" >&5
+echo "configure:2630: checking for vfork.h" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2579 "configure"
+#line 2635 "configure"
 #include "confdefs.h"
 #include <vfork.h>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:2584: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:2640: \"$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*
@@ -2605,18 +2661,18 @@ else
 fi
 
 echo $ac_n "checking for working vfork""... $ac_c" 1>&6
-echo "configure:2609: checking for working vfork" >&5
+echo "configure:2665: checking for working vfork" >&5
 if eval "test \"`echo '$''{'ac_cv_func_vfork_works'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   if test "$cross_compiling" = yes; then
   echo $ac_n "checking for vfork""... $ac_c" 1>&6
-echo "configure:2615: checking for vfork" >&5
+echo "configure:2671: checking for vfork" >&5
 if eval "test \"`echo '$''{'ac_cv_func_vfork'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2620 "configure"
+#line 2676 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char vfork(); below.  */
@@ -2639,7 +2695,7 @@ vfork();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2643: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2699: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_vfork=yes"
 else
@@ -2661,7 +2717,7 @@ fi
 ac_cv_func_vfork_works=$ac_cv_func_vfork
 else
   cat > conftest.$ac_ext <<EOF
-#line 2665 "configure"
+#line 2721 "configure"
 #include "confdefs.h"
 /* Thanks to Paul Eggert for this test.  */
 #include <stdio.h>
@@ -2756,7 +2812,7 @@ main() {
   }
 }
 EOF
-if { (eval echo configure:2760: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
+if { (eval echo configure:2816: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
 then
   ac_cv_func_vfork_works=yes
 else
@@ -2788,12 +2844,12 @@ fi
     for ac_func in _doprnt
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:2792: checking for $ac_func" >&5
+echo "configure:2848: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2797 "configure"
+#line 2853 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2816,7 +2872,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2820: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2876: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -2846,12 +2902,12 @@ done
     for ac_func in _doprnt
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:2850: checking for $ac_func" >&5
+echo "configure:2906: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2855 "configure"
+#line 2911 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2874,7 +2930,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2878: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2934: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -2902,19 +2958,19 @@ done
 
   for v in $vars; do
     echo $ac_n "checking for $v""... $ac_c" 1>&6
-echo "configure:2906: checking for $v" >&5
+echo "configure:2962: checking for $v" >&5
     if eval "test \"`echo '$''{'libiberty_cv_var_$v'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2911 "configure"
+#line 2967 "configure"
 #include "confdefs.h"
 int *p;
 int main() {
 extern int $v []; p = $v;
 ; return 0; }
 EOF
-if { (eval echo configure:2918: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2974: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "libiberty_cv_var_$v=yes"
 else
@@ -2940,12 +2996,12 @@ EOF
   for ac_func in $checkfuncs
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:2944: checking for $ac_func" >&5
+echo "configure:3000: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2949 "configure"
+#line 3005 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2968,7 +3024,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2972: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:3028: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -2992,6 +3048,54 @@ else
 fi
 done
 
+  echo $ac_n "checking whether canonicalize_file_name must be declared""... $ac_c" 1>&6
+echo "configure:3053: checking whether canonicalize_file_name must be declared" >&5
+if eval "test \"`echo '$''{'libiberty_cv_decl_needed_canonicalize_file_name'+set}'`\" = set"; then
+  echo $ac_n "(cached) $ac_c" 1>&6
+else
+  cat > conftest.$ac_ext <<EOF
+#line 3058 "configure"
+#include "confdefs.h"
+
+#include "confdefs.h"
+#include <stdio.h>
+#ifdef HAVE_STRING_H
+#include <string.h>
+#else
+#ifdef HAVE_STRINGS_H
+#include <strings.h>
+#endif
+#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+int main() {
+char *(*pfn) = (char *(*)) canonicalize_file_name
+; return 0; }
+EOF
+if { (eval echo configure:3080: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+  rm -rf conftest*
+  libiberty_cv_decl_needed_canonicalize_file_name=no
+else
+  echo "configure: failed program was:" >&5
+  cat conftest.$ac_ext >&5
+  rm -rf conftest*
+  libiberty_cv_decl_needed_canonicalize_file_name=yes
+fi
+rm -f conftest*
+fi
+
+echo "$ac_t""$libiberty_cv_decl_needed_canonicalize_file_name" 1>&6
+if test $libiberty_cv_decl_needed_canonicalize_file_name = yes; then
+  cat >> confdefs.h <<\EOF
+#define NEED_DECLARATION_CANONICALIZE_FILE_NAME 1
+EOF
+
+fi
+
 fi
 
 # Figure out which version of pexecute to use.
@@ -3004,21 +3108,21 @@ case "${host}" in
 esac
 
 
-for ac_hdr in stdlib.h unistd.h sys/stat.h sys/types.h
+for ac_hdr in unistd.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:3012: checking for $ac_hdr" >&5
+echo "configure:3116: checking for $ac_hdr" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 3017 "configure"
+#line 3121 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:3022: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:3126: \"$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*
@@ -3047,12 +3151,12 @@ done
 for ac_func in getpagesize
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:3051: checking for $ac_func" >&5
+echo "configure:3155: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 3056 "configure"
+#line 3160 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -3075,7 +3179,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:3079: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:3183: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -3100,7 +3204,7 @@ fi
 done
 
 echo $ac_n "checking for working mmap""... $ac_c" 1>&6
-echo "configure:3104: checking for working mmap" >&5
+echo "configure:3208: checking for working mmap" >&5
 if eval "test \"`echo '$''{'ac_cv_func_mmap_fixed_mapped'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -3108,7 +3212,7 @@ else
   ac_cv_func_mmap_fixed_mapped=no
 else
   cat > conftest.$ac_ext <<EOF
-#line 3112 "configure"
+#line 3216 "configure"
 #include "confdefs.h"
 
 /* Thanks to Mike Haertel and Jim Avera for this test.
@@ -3136,24 +3240,11 @@ else
 #include <fcntl.h>
 #include <sys/mman.h>
 
-#if HAVE_SYS_TYPES_H
-# include <sys/types.h>
-#endif
-
-#if HAVE_STDLIB_H
-# include <stdlib.h>
-#endif
-
-#if HAVE_SYS_STAT_H
-# include <sys/stat.h>
-#endif
-
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
-
 /* This mess was copied from the GNU getpagesize.h.  */
 #ifndef HAVE_GETPAGESIZE
+# ifdef HAVE_UNISTD_H
+#  include <unistd.h>
+# endif
 
 /* Assume that all systems that can run configure have sys/param.h.  */
 # ifndef HAVE_SYS_PARAM_H
@@ -3261,7 +3352,7 @@ main()
 }
 
 EOF
-if { (eval echo configure:3265: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
+if { (eval echo configure:3356: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
 then
   ac_cv_func_mmap_fixed_mapped=yes
 else
@@ -3285,7 +3376,7 @@ fi
 
 
 echo $ac_n "checking for working strncmp""... $ac_c" 1>&6
-echo "configure:3289: checking for working strncmp" >&5
+echo "configure:3380: checking for working strncmp" >&5
 if eval "test \"`echo '$''{'ac_cv_func_strncmp_works'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -3293,7 +3384,7 @@ else
   ac_cv_func_strncmp_works=no
 else
   cat > conftest.$ac_ext <<EOF
-#line 3297 "configure"
+#line 3388 "configure"
 #include "confdefs.h"
 
 /* Test by Jim Wilson and Kaveh Ghazi.
@@ -3357,7 +3448,7 @@ main ()
 }
 
 EOF
-if { (eval echo configure:3361: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
+if { (eval echo configure:3452: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
 then
   ac_cv_func_strncmp_works=yes
 else
diff --git a/libiberty/configure.in b/libiberty/configure.in
index 3d8dbf2..d170a9f 100644
--- a/libiberty/configure.in
+++ b/libiberty/configure.in
@@ -207,6 +207,7 @@ funcs="$funcs waitpid"
 vars="sys_errlist sys_nerr sys_siglist"
 
 checkfuncs="getrusage on_exit psignal strerror strsignal sysconf times sbrk gettimeofday"
+checkfuncs="$checkfuncs realpath canonicalize_file_name"
 
 # These are neither executed nor required, but they help keep
 # autoheader happy without adding a bunch of text to acconfig.h.
@@ -218,6 +219,7 @@ if test "x" = "y"; then
   AC_CHECK_FUNCS(strtod strtol strtoul tmpnam vasprintf vfprintf vprintf)
   AC_CHECK_FUNCS(vsprintf waitpid getrusage on_exit psignal strerror strsignal)
   AC_CHECK_FUNCS(sysconf times sbrk gettimeofday ffs)
+  AC_CHECK_FUNCS(realpath canonicalize_file_name)
   AC_DEFINE(HAVE_SYS_ERRLIST, 1, [Define if you have the sys_errlist variable.])
   AC_DEFINE(HAVE_SYS_NERR,    1, [Define if you have the sys_nerr variable.])
   AC_DEFINE(HAVE_SYS_SIGLIST, 1, [Define if you have the sys_siglist variable.])
@@ -424,6 +426,7 @@ if test -z "${setobjs}"; then
     fi
   done
   AC_CHECK_FUNCS($checkfuncs)
+  libiberty_NEED_DECLARATION(canonicalize_file_name)
 fi
 
 # Figure out which version of pexecute to use.
diff --git a/libiberty/functions.texi b/libiberty/functions.texi
index 18b2480..2c7b9e1 100644
--- a/libiberty/functions.texi
+++ b/libiberty/functions.texi
@@ -392,19 +392,38 @@ and a path ending in @code{/} returns the empty string after it.
 
 @end deftypefn
 
-@c make-relative-prefix.c:24
-@deftypefn Extension {const char*} make_relative_prefix (const char *@var{progname}, const char *@var{bin_prefix}, const char *@var{prefix})
+@c lrealpath.c:25
+@deftypefn Replacement {const char*} lrealpath (const char *@var{name})
+
+Given a pointer to a string containing a pathname, returns a canonical
+version of the filename.  Symlinks will be resolved, and ``.'' and ``..''
+components will be simplified.  The returned value will be allocated using
+@code{xmalloc} or @code{malloc}.
 
-Given three strings @var{progname}, @var{bin_prefix}, @var{prefix}, return a string
-that gets to @var{prefix} starting with the directory portion of @var{progname} and
-a relative pathname of the difference between @var{bin_prefix} and @var{prefix}.
+@end deftypefn
 
-For example, if @var{bin_prefix} is @code{/alpha/beta/gamma/gcc/delta}, @var{prefix}
-is @code{/alpha/beta/gamma/omega/}, and @var{progname} is @code{/red/green/blue/gcc},
-then this function will return @code{/red/green/blue/../../omega/}.
+@c make-relative-prefix.c:24
+@deftypefn Extension {const char*} make_relative_prefix (const char *@var{progname}, const char *@var{bin_prefix}, const char *@var{prefix})
 
-The return value is normally allocated via @code{malloc}.  If no relative prefix
-can be found, return @code{NULL}.
+Given three paths @var{progname}, @var{bin_prefix}, @var{prefix},
+return the path that is in the same position relative to
+@var{progname}'s directory as @var{prefix} is relative to
+@var{bin_prefix}.  That is, a string starting with the directory
+portion of @var{progname}, followed by a relative pathname of the
+difference between @var{bin_prefix} and @var{prefix}.
+
+If @var{progname} does not contain any directory separators,
+@code{make_relative_prefix} will search @env{PATH} to find a program
+named @var{progname}.  Also, if @var{progname} is a symbolic link,
+the symbolic link will be resolved.
+
+For example, if @var{bin_prefix} is @code{/alpha/beta/gamma/gcc/delta},
+@var{prefix} is @code{/alpha/beta/gamma/omega/}, and @var{progname} is
+@code{/red/green/blue/gcc}, then this function will return
+@code{/red/green/blue/../../omega/}.
+
+The return value is normally allocated via @code{malloc}.  If no
+relative prefix can be found, return @code{NULL}.
 
 @end deftypefn
 
diff --git a/libiberty/lrealpath.c b/libiberty/lrealpath.c
new file mode 100644
index 0000000..b001b38
--- /dev/null
+++ b/libiberty/lrealpath.c
@@ -0,0 +1,128 @@
+/* Libiberty realpath.  Like realpath, but more consistent behavior.
+   Based on gdb_realpath from GDB.
+
+   Copyright 2003 Free Software Foundation, Inc.
+
+   This file is part of the libiberty library.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+/*
+
+@deftypefn Replacement {const char*} lrealpath (const char *@var{name})
+
+Given a pointer to a string containing a pathname, returns a canonical
+version of the filename.  Symlinks will be resolved, and ``.'' and ``..''
+components will be simplified.  The returned value will be allocated using
+@code{malloc}, or @code{NULL} will be returned on a memory allocation error.
+
+@end deftypefn
+
+*/
+
+#include "config.h"
+#include "ansidecl.h"
+#include "libiberty.h"
+
+#ifdef HAVE_LIMITS_H
+#include <limits.h>
+#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+
+/* On GNU libc systems the declaration is only visible with _GNU_SOURCE.  */
+#if defined(HAVE_CANONICALIZE_FILE_NAME) \
+    && defined(NEED_DECLARATION_CANONICALIZE_FILE_NAME)
+extern char *canonicalize_file_name (const char *);
+#endif
+
+#if defined(HAVE_REALPATH)
+# if defined (PATH_MAX)
+#  define REALPATH_LIMIT PATH_MAX
+# else
+#  if defined (MAXPATHLEN)
+#   define REALPATH_LIMIT MAXPATHLEN
+#  endif
+# endif
+#endif
+
+char *
+lrealpath (filename)
+     const char *filename;
+{
+  /* Method 1: The system has a compile time upper bound on a filename
+     path.  Use that and realpath() to canonicalize the name.  This is
+     the most common case.  Note that, if there isn't a compile time
+     upper bound, you want to avoid realpath() at all costs.  */
+#if defined(REALPATH_LIMIT)
+  {
+    char buf[REALPATH_LIMIT];
+    const char *rp = realpath (filename, buf);
+    if (rp == NULL)
+      rp = filename;
+    return strdup (rp);
+  }
+#endif /* REALPATH_LIMIT */
+
+  /* Method 2: The host system (i.e., GNU) has the function
+     canonicalize_file_name() which malloc's a chunk of memory and
+     returns that, use that.  */
+#if defined(HAVE_CANONICALIZE_FILE_NAME)
+  {
+    char *rp = canonicalize_file_name (filename);
+    if (rp == NULL)
+      return strdup (filename);
+    else
+      return rp;
+  }
+#endif
+
+  /* Method 3: Now we're getting desperate!  The system doesn't have a
+     compile time buffer size and no alternative function.  Query the
+     OS, using pathconf(), for the buffer limit.  Care is needed
+     though, some systems do not limit PATH_MAX (return -1 for
+     pathconf()) making it impossible to pass a correctly sized buffer
+     to realpath() (it could always overflow).  On those systems, we
+     skip this.  */
+#if defined (HAVE_REALPATH) && defined (HAVE_UNISTD_H)
+  {
+    /* Find out the max path size.  */
+    long path_max = pathconf ("/", _PC_PATH_MAX);
+    if (path_max > 0)
+      {
+	/* PATH_MAX is bounded.  */
+	char *buf, *rp, *ret;
+	buf = malloc (path_max);
+	if (buf == NULL)
+	  return NULL;
+	rp = realpath (filename, buf);
+	ret = strdup (rp ? rp : filename);
+	free (buf);
+	return ret;
+      }
+  }
+#endif
+
+  /* This system is a lost cause, just duplicate the filename.  */
+  return strdup (filename);
+}
diff --git a/libiberty/make-relative-prefix.c b/libiberty/make-relative-prefix.c
index c208cdc..dc4f8d5 100644
--- a/libiberty/make-relative-prefix.c
+++ b/libiberty/make-relative-prefix.c
@@ -23,16 +23,25 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 
 @deftypefn Extension {const char*} make_relative_prefix (const char *@var{progname}, const char *@var{bin_prefix}, const char *@var{prefix})
 
-Given three strings @var{progname}, @var{bin_prefix}, @var{prefix}, return a string
-that gets to @var{prefix} starting with the directory portion of @var{progname} and
-a relative pathname of the difference between @var{bin_prefix} and @var{prefix}.
-
-For example, if @var{bin_prefix} is @code{/alpha/beta/gamma/gcc/delta}, @var{prefix}
-is @code{/alpha/beta/gamma/omega/}, and @var{progname} is @code{/red/green/blue/gcc},
-then this function will return @code{/red/green/blue/../../omega/}.
-
-The return value is normally allocated via @code{malloc}.  If no relative prefix
-can be found, return @code{NULL}.
+Given three paths @var{progname}, @var{bin_prefix}, @var{prefix},
+return the path that is in the same position relative to
+@var{progname}'s directory as @var{prefix} is relative to
+@var{bin_prefix}.  That is, a string starting with the directory
+portion of @var{progname}, followed by a relative pathname of the
+difference between @var{bin_prefix} and @var{prefix}.
+
+If @var{progname} does not contain any directory separators,
+@code{make_relative_prefix} will search @env{PATH} to find a program
+named @var{progname}.  Also, if @var{progname} is a symbolic link,
+the symbolic link will be resolved.
+
+For example, if @var{bin_prefix} is @code{/alpha/beta/gamma/gcc/delta},
+@var{prefix} is @code{/alpha/beta/gamma/omega/}, and @var{progname} is
+@code{/red/green/blue/gcc}, then this function will return
+@code{/red/green/blue/../../omega/}.
+
+The return value is normally allocated via @code{malloc}.  If no
+relative prefix can be found, return @code{NULL}.
 
 @end deftypefn
 
@@ -223,19 +232,14 @@ make_relative_prefix (progname, bin_prefix, prefix)
   int prog_num, bin_num, prefix_num;
   int i, n, common;
   int needed_len;
-  char *ret, *ptr;
+  char *ret, *ptr, *full_progname = NULL;
 
   if (progname == NULL || bin_prefix == NULL || prefix == NULL)
     return NULL;
 
-  prog_dirs = split_directories (progname, &prog_num);
-  bin_dirs = split_directories (bin_prefix, &bin_num);
-  if (bin_dirs == NULL || prog_dirs == NULL)
-    return NULL;
-
   /* If there is no full pathname, try to find the program by checking in each
      of the directories specified in the PATH environment variable.  */
-  if (prog_num == 1)
+  if (lbasename (progname) == progname)
     {
       char *temp;
 
@@ -278,14 +282,7 @@ make_relative_prefix (progname, bin_prefix, prefix)
 #endif
 		      )
 		    {
-		      free_split_directories (prog_dirs);
 		      progname = nstore;
-		      prog_dirs = split_directories (progname, &prog_num);
-		      if (prog_dirs == NULL)
-			{
-			  free_split_directories (bin_dirs);
-			  return NULL;
-			}
 		      break;
 		    }
 
@@ -299,6 +296,16 @@ make_relative_prefix (progname, bin_prefix, prefix)
 	}
     }
 
+  full_progname = lrealpath (progname);
+  if (full_progname == NULL)
+    return NULL;
+
+  prog_dirs = split_directories (full_progname, &prog_num);
+  bin_dirs = split_directories (bin_prefix, &bin_num);
+  free (full_progname);
+  if (bin_dirs == NULL || prog_dirs == NULL)
+    return NULL;
+
   /* Remove the program name from comparison of directory names.  */
   prog_num--;