[newlib-cygwin] Cygwin: Restore setting CC and CXX Makefile variables

[Jon TURNEY <jturney@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=7fa743ca9468d7725953ebdfb0d0b53ad126c14c

commit 7fa743ca9468d7725953ebdfb0d0b53ad126c14c
Author: Jon Turney <jon.turney@dronecode.org.uk>
Date:   Tue Oct 27 15:31:06 2020 +0000

    Cygwin: Restore setting CC and CXX Makefile variables
    
    b55e3f19 was a bit too aggressive in dropping, rather than just
    un-exporting these Makefile variables.  We need to set these to the
    configured host compiler if we are cross-compiling, otherwise they
    default to the build compiler.
    
    Also export CC to the mkvers.sh script (which requires it since
    4eca5e6a).  It's unclear why we can't just cause windres to use the
    build 'cpp' as the pre-processor there.

Diff:
---
 winsup/cygserver/Makefile.in | 3 +++
 winsup/cygwin/Makefile.in    | 4 ++++
 winsup/utils/Makefile.in     | 3 +++
 3 files changed, 10 insertions(+)

diff --git a/winsup/cygserver/Makefile.in b/winsup/cygserver/Makefile.in
index 7b250dd68..65c402517 100644
--- a/winsup/cygserver/Makefile.in
+++ b/winsup/cygserver/Makefile.in
@@ -11,6 +11,9 @@ target_builddir:=@target_builddir@
 winsup_srcdir:=@winsup_srcdir@
 configure_args=@configure_args@
 
+CC:=@CC@
+CXX:=@CXX@
+
 CFLAGS:=@CFLAGS@
 override CXXFLAGS=@CXXFLAGS@
 override CXXFLAGS+=-MMD -Wimplicit-fallthrough=5 -Werror -D__OUTSIDE_CYGWIN__ -DSYSCONFDIR="\"$(sysconfdir)\""
diff --git a/winsup/cygwin/Makefile.in b/winsup/cygwin/Makefile.in
index dad526b74..f6236d909 100644
--- a/winsup/cygwin/Makefile.in
+++ b/winsup/cygwin/Makefile.in
@@ -14,6 +14,9 @@ target_builddir:=@target_builddir@
 winsup_srcdir:=@winsup_srcdir@
 configure_args=@configure_args@
 
+CC:=@CC@
+CXX:=@CXX@
+
 CFLAGS?=@CFLAGS@
 CXXFLAGS?=@CXXFLAGS@
 INCLUDES?=@INCLUDES@
@@ -773,6 +776,7 @@ src_files := $(foreach dir,$(VPATH),$(find_src_files))
 # second, so version.cc is always older than winver.o
 version.cc: mkvers.sh include/cygwin/version.h winver.rc $(src_files)
 	@echo "Making version.cc and winver.o";\
+	export CC="${CC}";\
 	/bin/sh ${word 1,$^} ${word 2,$^} ${word 3,$^} $(WINDRES) ${CFLAGS} -I${srcdir}/include
 $(VERSION_OFILES): version.cc
 
diff --git a/winsup/utils/Makefile.in b/winsup/utils/Makefile.in
index add29d10f..e21874027 100644
--- a/winsup/utils/Makefile.in
+++ b/winsup/utils/Makefile.in
@@ -11,6 +11,9 @@ target_builddir:=@target_builddir@
 winsup_srcdir:=@winsup_srcdir@
 configure_args=@configure_args@
 
+CC:=@CC@
+CXX:=@CXX@
+
 CFLAGS_COMMON=-Wimplicit-fallthrough=4 -Werror
 CFLAGS:=@CFLAGS@
 CXXFLAGS:=@CXXFLAGS@