libtool: add icl.exe support

A logical continuation of Automake commit
c40e27e1c2a60f58e72e65d73d808f782d55494a to provide
Windows ICC support similar as already done for MSVC.

Resolves bug 26484.

* m4/libtool.m4: Treat icl.exe equivalently to cl.exe.

Copyright-paperwork-exempt: Yes

2 files changed, 19 insertions, 16 deletions

diff --git a/NEWS b/NEWS
index 41ae0310..bdcda35d 100644
--- a/NEWS
+++ b/NEWS
@@ -10,6 +10,9 @@ NEWS - list of user-visible changes between releases of GNU Libtool
 
   - Gnulib testsuite is enabled and run during 'make check'.
 
+  - Support the Windows version of the Intel C Compiler (icl) in
+    libtool script.
+
 ** Important incompatible changes:
 
   - Libtool changed ARFLAGS/AR_FLAGS default from 'cru' to 'cr'.
diff --git a/m4/libtool.m4 b/m4/libtool.m4
index 597c6042..23edacec 100644
--- a/m4/libtool.m4
+++ b/m4/libtool.m4
@@ -219,8 +219,8 @@ esac
 ofile=libtool
 can_build_shared=yes
 
-# All known linkers require a '.a' archive for static linking (except MSVC,
-# which needs '.lib').
+# All known linkers require a '.a' archive for static linking (except MSVC and
+# ICC, which need '.lib').
 libext=a
 
 with_gnu_ld=$lt_cv_prog_gnu_ld
@@ -2587,8 +2587,8 @@ m4_if([$1], [],[
     dynamic_linker='Win32 ld.exe'
     ;;
 
-  *,cl*)
-    # Native MSVC
+  *,cl* | *,icl*)
+    # Native MSVC or ICC
     libname_spec='$name'
     soname_spec='$libname`echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext'
     library_names_spec='$libname.dll.lib'
@@ -2644,7 +2644,7 @@ m4_if([$1], [],[
     ;;
 
   *)
-    # Assume MSVC wrapper
+    # Assume MSVC and ICC wrapper
     library_names_spec='$libname`echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext $libname.lib'
     dynamic_linker='Win32 ld.exe'
     ;;
@@ -4032,7 +4032,7 @@ for ac_symprfx in "" "_"; do
   if test "$lt_cv_nm_interface" = "MS dumpbin"; then
     # Fake it for dumpbin and say T for any non-static function,
     # D for any global variable and I for any imported variable.
-    # Also find C++ and __fastcall symbols from MSVC++,
+    # Also find C++ and __fastcall symbols from MSVC++ or ICC,
     # which start with @ or ?.
     lt_cv_sys_global_symbol_pipe="$AWK ['"\
 "     {last_section=section; section=\$ 3};"\
@@ -4949,7 +4949,7 @@ m4_if([$1], [CXX], [
     ;;
   cygwin* | mingw* | cegcc*)
     case $cc_basename in
-    cl*)
+    cl* | icl*)
       _LT_TAGVAR(exclude_expsyms, $1)='_NULL_IMPORT_DESCRIPTOR|_IMPORT_DESCRIPTOR_.*'
       ;;
     *)
@@ -5006,15 +5006,15 @@ dnl Note also adjust exclude_expsyms for C++ above.
 
   case $host_os in
   cygwin* | mingw* | pw32* | cegcc*)
-    # FIXME: the MSVC++ port hasn't been tested in a loooong time
+    # FIXME: the MSVC++ and ICC port hasn't been tested in a loooong time
     # When not using gcc, we currently assume that we are using
-    # Microsoft Visual C++.
+    # Microsoft Visual C++ or Intel C++ Compiler.
     if test yes != "$GCC"; then
       with_gnu_ld=no
     fi
     ;;
   interix*)
-    # we just hope/assume this is gcc and not c89 (= MSVC++)
+    # we just hope/assume this is gcc and not c89 (= MSVC++ or ICC)
     with_gnu_ld=yes
     ;;
   openbsd* | bitrig*)
@@ -5579,12 +5579,12 @@ _LT_EOF
 
     cygwin* | mingw* | pw32* | cegcc*)
       # When not using gcc, we currently assume that we are using
-      # Microsoft Visual C++.
+      # Microsoft Visual C++ or Intel C++ Compiler.
       # hardcode_libdir_flag_spec is actually meaningless, as there is
       # no search path for DLLs.
       case $cc_basename in
-      cl*)
-	# Native MSVC
+      cl* | icl*)
+	# Native MSVC or ICC
 	_LT_TAGVAR(hardcode_libdir_flag_spec, $1)=' '
 	_LT_TAGVAR(allow_undefined_flag, $1)=unsupported
 	_LT_TAGVAR(always_export_symbols, $1)=yes
@@ -5625,7 +5625,7 @@ _LT_EOF
           fi'
 	;;
       *)
-	# Assume MSVC wrapper
+	# Assume MSVC and ICC wrapper
 	_LT_TAGVAR(hardcode_libdir_flag_spec, $1)=' '
 	_LT_TAGVAR(allow_undefined_flag, $1)=unsupported
 	# Tell ltmain to make .lib files, not .a files.
@@ -6655,8 +6655,8 @@ if test yes != "$_lt_caught_CXX_error"; then
 
       cygwin* | mingw* | pw32* | cegcc*)
 	case $GXX,$cc_basename in
-	,cl* | no,cl*)
-	  # Native MSVC
+	,cl* | no,cl* | ,icl* | no,icl*)
+	  # Native MSVC or ICC
 	  # hardcode_libdir_flag_spec is actually meaningless, as there is
 	  # no search path for DLLs.
 	  _LT_TAGVAR(hardcode_libdir_flag_spec, $1)=' '