tools/libxl: do not use `-c -E` compiler options together

It makes no sense to request for preprocessor only output and also request
object file generation.  Fix the _libxl.api-for-check target to only use
-E (preprocessor output).

Also Clang 20.0 reports an error if both options are used.

Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Fixes: 2862bf5b6c81 ('libxl: enforce prohibitions of internal callers')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
(cherry picked from commit a235f856e4bbd270b085590e1f5fc9599234dcdf)

diff --git a/tools/libs/light/Makefile b/tools/libs/light/Makefile
index 37e4d167098690b1d40d9fb07a185c0950a4cc83..b690d921593dda67dfbaa6b7701c2c4bab604f46 100644 (file)
--- a/tools/libs/light/Makefile
+++ b/tools/libs/light/Makefile
@@ -195,7 +195,7 @@ libxl.api-ok: check-libxl-api-rules _libxl.api-for-check
        touch $@
 
 _libxl.api-for-check: $(XEN_INCLUDE)/libxl.h
-       $(CC) $(CPPFLAGS) $(CFLAGS) -c -E $< $(APPEND_CFLAGS) \
+       $(CC) $(CPPFLAGS) $(CFLAGS) -E $< $(APPEND_CFLAGS) \
                -DLIBXL_EXTERNAL_CALLERS_ONLY=LIBXL_EXTERNAL_CALLERS_ONLY \
                >$@.new
        mv -f $@.new $@