Patch for cygwin: silence cwrapper compilation warnings

[Charles Wilson]

Now that configure doesn't generate libtool until late in the game (when 
LT_OUTPUT is not used), the package CFLAGS determined during the rest of 
configure are added to LTCFLAGS, and used to compile the cwrapper.

In one case, the project used -Wall -Werror -std=c99 (which turns on 
__STRICT_ANSI__).  This led to a number of problems:

(1) .warning: string length `4368' is greater than the
length `4095' ISO C99 compilers are required to support

e.g. we can't put the entire wrapper script into a single string

(2) warning: implicit declaration of function `realpath'

Posix says realpath is declared when #include <stdlib>
Strict ansi says no.

These warnings, coupled with -Werror, means that libtool fails compile 
the wrapper executable.  However, that error is not detected, and 
libtool continues:

(3) strip: './foo.exe': No such file

The attached patch addresses #1 and #2, but not #3.  Reported by Yaakov 
Selkowitz.  I'm not sure if all the documentation needs to be duplicated 
for all three functions, but...

Test suite on cygwin in progress.

--
Chuck

2008-04-25  Charles Wilson  <...>

        Ensure cwrapper compiles without warnings under -std=c99:

        * libltdl/config/ltmain.m4sh (func_emit_wrapper_part1):
        new function.
        (func_emit_wrapper_part2): new function.
        (func_emit_wrapper): delegate to new functions.
        (func_emit_cwrapperexe_src) [__CYGWIN__ && __STRICT_ANSI__]:
        ensure realpath is declared.
        (func_emit_cwrapperexe_src): declare two different strings
        to each hold part of the wrapper script content. Initialize
        using new func_emit_wrapper_partX functions.
        (func_emit_cwrapperexe_src) [main]: when emitting wrapper
        script content, use both strings.

diff --git a/libltdl/config/ltmain.m4sh b/libltdl/config/ltmain.m4sh
index ac334dc..60cad1f 100644
--- a/libltdl/config/ltmain.m4sh
+++ b/libltdl/config/ltmain.m4sh
@@ -2249,9 +2249,9 @@ func_extract_archives ()
 
 
 
-# func_emit_wrapper arg
+# func_emit_wrapper_part1 arg
 #
-# emit a libtool wrapper script on stdout
+# emit the first part of a libtool wrapper script on stdout
 # don't directly open a file because we may want to
 # incorporate the script contents within a cygwin/mingw
 # wrapper executable.  Must ONLY be called from within
@@ -2263,11 +2263,11 @@ func_extract_archives ()
 # will assume that the directory in which it is stored is
 # the '.lib' directory.  This is a cygwin/mingw-specific
 # behavior.
-func_emit_wrapper ()
+func_emit_wrapper_part1 ()
 {
-       func_emit_wrapper_arg1=no
+       func_emit_wrapper_part1_arg1=no
        if test -n "$1" ; then
-         func_emit_wrapper_arg1=$1
+         func_emit_wrapper_part1_arg1=$1
        fi
 
        $ECHO "\
@@ -2352,10 +2352,36 @@ else
     file=\`\$ECHO \"X\$file\" | \$Xsed -e 's%^.*/%%'\`
     file=\`ls -ld \"\$thisdir/\$file\" | ${SED} -n 's/.*-> //p'\`
   done
+"
+}
+# end: func_emit_wrapper_part1
+
+# func_emit_wrapper_part2 arg
+#
+# emit the second part of a libtool wrapper script on stdout
+# don't directly open a file because we may want to
+# incorporate the script contents within a cygwin/mingw
+# wrapper executable.  Must ONLY be called from within
+# func_mode_link because it depends on a number of variable
+# set therein.
+#
+# arg is the value that the WRAPPER_SCRIPT_BELONGS_IN_OBJDIR
+# variable will take.  If 'yes', then the emitted script
+# will assume that the directory in which it is stored is
+# the '.lib' directory.  This is a cygwin/mingw-specific
+# behavior.
+func_emit_wrapper_part2 ()
+{
+       func_emit_wrapper_part2_arg1=no
+       if test -n "$1" ; then
+         func_emit_wrapper_part2_arg1=$1
+       fi
+
+       $ECHO "\
 
   # Usually 'no', except on cygwin/mingw when embedded into
   # the cwrapper.
-  WRAPPER_SCRIPT_BELONGS_IN_OBJDIR=$func_emit_wrapper_arg1
+  WRAPPER_SCRIPT_BELONGS_IN_OBJDIR=$func_emit_wrapper_part2_arg1
   if test \"\$WRAPPER_SCRIPT_BELONGS_IN_OBJDIR\" = \"yes\"; then
     # special case for '.'
     if test \"\$thisdir\" = \".\"; then
@@ -2472,7 +2498,36 @@ else
 fi\
 "
 }
-# end: func_emit_wrapper
+# end: func_emit_wrapper_part2
+
+
+# func_emit_wrapper arg
+#
+# emit a libtool wrapper script on stdout
+# don't directly open a file because we may want to
+# incorporate the script contents within a cygwin/mingw
+# wrapper executable.  Must ONLY be called from within
+# func_mode_link because it depends on a number of variable
+# set therein.
+#
+# arg is the value that the WRAPPER_SCRIPT_BELONGS_IN_OBJDIR
+# variable will take.  If 'yes', then the emitted script
+# will assume that the directory in which it is stored is
+# the '.lib' directory.  This is a cygwin/mingw-specific
+# behavior.
+func_emit_wrapper ()
+{
+       func_emit_wrapper_arg1=no
+       if test -n "$1" ; then
+         func_emit_wrapper_arg1=$1
+       fi
+
+       # split this up so that func_emit_cwrapperexe_src
+       # can call each part independently.
+       func_emit_wrapper_part1 "${func_emit_wrapper_arg1}"
+       func_emit_wrapper_part2 "${func_emit_wrapper_arg2}"
+}
+
 
 # func_emit_cwrapperexe_src
 # emit the source code for a wrapper executable on stdout
@@ -2509,6 +2564,9 @@ EOF
 # include <stdint.h>
 # ifdef __CYGWIN__
 #  include <io.h>
+#  ifdef __STRICT_ANSI__
+char *realpath (const char *, char *);
+#  endif
 # endif
 #endif
 #include <malloc.h>
@@ -2616,10 +2674,18 @@ int check_executable (const char *path);
 char *strendzap (char *str, const char *pat);
 void lt_fatal (const char *message, ...);
 
-static const char *script_text =
+static const char *script_text_part1 =
 EOF
 
-           func_emit_wrapper yes |
+           func_emit_wrapper_part1 yes |
+               $SED -e 's/\([\\"]\)/\\\1/g' \
+                    -e 's/^/  "/' -e 's/$/\\n"/'
+           echo ";"
+           cat <<EOF
+
+static const char *script_text_part2 = 
+EOF
+           func_emit_wrapper_part2 yes |
                $SED -e 's/\([\\"]\)/\\\1/g' \
                     -e 's/^/  "/' -e 's/$/\\n"/'
            echo ";"
@@ -2658,7 +2724,8 @@ EOF
              esac
 
            cat <<EOF
-         printf ("%s", script_text);
+         printf ("%s", script_text_part1);
+         printf ("%s", script_text_part2);
          return 0;
        }
     }
@@ -2750,7 +2817,8 @@ EOF
     {
       lt_fatal ("Could not open %s for writing", newargz[1]);
     }
-  fprintf (shwrapper, "%s", script_text);
+  fprintf (shwrapper, "%s", script_text_part1);
+  fprintf (shwrapper, "%s", script_text_part2);
   fclose (shwrapper);
 
   make_executable (newargz[1]);