[PATCH] build: Use -nostdinc generating macro_list [PR109522]

[Xi Ruoyao <xry111@xry111.site>]

This prevents a spurious message building a cross-compiler when target
libc is not installed yet:

    cc1: error: no include path in which to search for stdc-predef.h

As stdc-predef.h was added to define __STDC_* macros by libc, it's
unlikely the header will ever contain some bad definitions w/o "__"
prefix so it should be safe.

gcc/ChangeLog:

	PR other/109522
	* Makefile.in (s-macro_list): Pass -nostdinc to
	$(GCC_FOR_TARGET).
---
 gcc/Makefile.in | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index ad9a5d94cd0..eb26d5c7be5 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -3215,7 +3215,7 @@ install-gcc-tooldir:
 
 macro_list: s-macro_list; @true
 s-macro_list : $(GCC_PASSES) cc1$(exeext)
-	echo | $(GCC_FOR_TARGET) -E -dM - | \
+	echo | $(GCC_FOR_TARGET) -nostdinc -E -dM - | \
 	  sed -n -e 's/^#define \([^_][a-zA-Z0-9_]*\).*/\1/p' \
 		 -e 's/^#define \(_[^_A-Z][a-zA-Z0-9_]*\).*/\1/p' | \
 	  sort -u > tmp-macro_list
-- 
2.40.0