[PATCH] Check for clang-cl.exe after cl.exe

> clang-cl is an alternative command-line interface to Clang, designed
> for compatibility with the Visual C++ compiler, cl.exe.

https://clang.llvm.org/docs/UsersManual.html#clang-cl
---
 lib/autoconf/c.m4                         | 5 ++++-
 tests/data/gnulib_std_gnu11_2020_08_17.m4 | 5 ++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/lib/autoconf/c.m4 b/lib/autoconf/c.m4
index 689e506d..fa6965b3 100644
--- a/lib/autoconf/c.m4
+++ b/lib/autoconf/c.m4
@@ -483,6 +483,9 @@ fi
 if test -z "$CC"; then
   AC_CHECK_TOOLS(CC, cl.exe)
 fi
+if test -z "$CC"; then
+  AC_CHECK_TOOLS(CC, clang-cl.exe)
+fi
 if test -z "$CC"; then
   AC_CHECK_TOOL(CC, clang)
 fi
@@ -699,7 +702,7 @@ if test -z "$CXX"; then
   else
     AC_CHECK_TOOLS(CXX,
 		   [m4_default([$1],
-			       [g++ c++ gpp aCC CC cxx cc++ cl.exe FCC KCC RCC xlC_r xlC clang++])],
+			       [g++ c++ gpp aCC CC cxx cc++ cl.exe clang-cl.exe FCC KCC RCC xlC_r xlC clang++])],
 		   g++)
   fi
 fi
diff --git a/tests/data/gnulib_std_gnu11_2020_08_17.m4 b/tests/data/gnulib_std_gnu11_2020_08_17.m4
index 21f7cc7a..77ec5558 100644
--- a/tests/data/gnulib_std_gnu11_2020_08_17.m4
+++ b/tests/data/gnulib_std_gnu11_2020_08_17.m4
@@ -58,6 +58,9 @@ fi
 if test -z "$CC"; then
   AC_CHECK_TOOLS(CC, cl.exe)
 fi
+if test -z "$CC"; then
+  AC_CHECK_TOOLS(CC, clang-cl.exe)
+fi
 if test -z "$CC"; then
   AC_CHECK_TOOL(CC, clang)
 fi
@@ -126,7 +129,7 @@ if test -z "$CXX"; then
   else
     AC_CHECK_TOOLS(CXX,
 		   [m4_default([$1],
-			       [g++ c++ gpp aCC CC cxx cc++ cl.exe FCC KCC RCC xlC_r xlC clang++])],
+			       [g++ c++ gpp aCC CC cxx cc++ cl.exe clang-cl.exe FCC KCC RCC xlC_r xlC clang++])],
 		   g++)
   fi
 fi
-- 
2.51.2