bpo-26317: Build Problem with GCC + Macintosh OS X 10.11 El Capitain

Mac/Makefile.in

@@ -21,6 +21,7 @@ PYTHONFRAMEWORK=@PYTHONFRAMEWORK@
 PYTHONFRAMEWORKIDENTIFIER=@PYTHONFRAMEWORKIDENTIFIER@
 LIPO_32BIT_FLAGS=@LIPO_32BIT_FLAGS@
 CC=@CC@
+OBJC=@OBJC@
 MACOSX_DEPLOYMENT_TARGET=@CONFIGURE_MACOSX_DEPLOYMENT_TARGET@
 export MACOSX_DEPLOYMENT_TARGET
 

Mac/PythonLauncher/Makefile.in

@@ -1,5 +1,7 @@
 CC=@CC@
 LD=@CC@
+OBJC=@OBJC@
+OBJCFLAFS=@OBJCFLAGS@
 BASECFLAGS=@BASECFLAGS@
 OPT=@OPT@
 CFLAGS=@CFLAGS@ $(BASECFLAGS) $(OPT)
@@ -52,25 +54,25 @@ Python\ Launcher.app:  Info.plist \
 	cp -R $(srcdir)/English.lproj "Python Launcher.app/Contents/Resources"
 
 FileSettings.o: $(srcdir)/FileSettings.m
-	$(CC) $(CFLAGS) -o $@ -c $(srcdir)/FileSettings.m
+	$(OBJC) $(CFLAGS) -o $@ -c $(srcdir)/FileSettings.m
 
 MyAppDelegate.o: $(srcdir)/MyAppDelegate.m
-	$(CC) $(CFLAGS) -o $@ -c $(srcdir)/MyAppDelegate.m
+	$(OBJC) $(CFLAGS) -o $@ -c $(srcdir)/MyAppDelegate.m
 
 MyDocument.o: $(srcdir)/MyDocument.m
-	$(CC) $(CFLAGS) -o $@ -c $(srcdir)/MyDocument.m
+	$(OBJC) $(CFLAGS) -o $@ -c $(srcdir)/MyDocument.m
 
 PreferencesWindowController.o: $(srcdir)/PreferencesWindowController.m
-	$(CC) $(CFLAGS) -o $@ -c $(srcdir)/PreferencesWindowController.m
+	$(OBJC) $(CFLAGS) -o $@ -c $(srcdir)/PreferencesWindowController.m
 
 doscript.o: $(srcdir)/doscript.m
-	$(CC) $(CFLAGS) -o $@ -c $(srcdir)/doscript.m
+	$(OBJC) $(CFLAGS) -o $@ -c $(srcdir)/doscript.m
 
 main.o: $(srcdir)/main.m
-	$(CC) $(CFLAGS) -o $@ -c $(srcdir)/main.m
+	$(OBJC) $(CFLAGS) -o $@ -c $(srcdir)/main.m
 
 Python\ Launcher: $(OBJECTS)
-	$(CC) $(LDFLAGS) -o "Python Launcher" $(OBJECTS) -framework AppKit -framework Carbon
+	$(OBJC) $(LDFLAGS) -o "Python Launcher" $(OBJECTS) -framework AppKit -framework Carbon
 
 Info.plist: $(srcdir)/Info.plist.in
 	sed 's/%VERSION%/'"`$(RUNSHARED) $(BUILDPYTHON) -c 'import platform; print(platform.python_version())'`"'/g' < $(srcdir)/Info.plist.in > Info.plist

Makefile.pre.in

@@ -35,6 +35,7 @@ abs_builddir=	@abs_builddir@
 
 CC=		@CC@
 CXX=		@CXX@
+OBJC=		@OBJC@
 MAINCC=		@MAINCC@
 LINKCC=		@LINKCC@
 AR=		@AR@
@@ -593,12 +594,22 @@ $(srcdir)/Modules/_blake2/blake2s_impl.c: $(srcdir)/Modules/_blake2/blake2b_impl
 	$(PYTHON_FOR_REGEN) $(srcdir)/Modules/_blake2/blake2b2s.py
 	$(PYTHON_FOR_REGEN) $(srcdir)/Tools/clinic/clinic.py -f $@
 
+# _scproxy.o needs to be built outside of setup.py so that we can force
+# the use of the OBJC compiler when the CC compiler is different. For
+# example, it allows _scproxy.c to be compiled using the clang compiler
+# while the rest of the project uses the GNU C compiler.
+#
+# see issue #26317 for details
+@SCPROXY@Modules/_scproxy.o:	$(srcdir)/Modules/_scproxy.c $(srcdir)/Include/Python.h
+@SCPROXY@	$(OBJC) -c $(CCSHARED) $(PY_CORE_CFLAGS) -o $@ $<
+@NOSCPROXY@.PHONY:	Modules/_scproxy.o
+
 # Build the shared modules
 # Under GNU make, MAKEFLAGS are sorted and normalized; the 's' for
 # -s, --silent or --quiet is always the first char.
 # Under BSD make, MAKEFLAGS might be " -s -v x=y".
 # Ignore macros passed by GNU make, passed after --
-sharedmods: $(BUILDPYTHON) pybuilddir.txt Modules/_math.o
+sharedmods: $(BUILDPYTHON) pybuilddir.txt Modules/_math.o Modules/_scproxy.o
 	@case "`echo X $$MAKEFLAGS | sed 's/^X //;s/ -- .*//'`" in \
 	    *\ -s*|s*) quiet="-q";; \
 	    *) quiet="";; \

Misc/NEWS.d/next/Build/2019-05-14-05-35-14.bpo-26317.no8mw-.rst

@@ -0,0 +1 @@
+The OBJC and OBJCXX standard command line options for the configure script are now supported. This is required to support building on Mac OS X using the GNU compiler for everything except the system-specific source files that include system headers that are incompatible with the GNU compiler (e.g. PythonLauncher and the _scproxy module).

aclocal.m4

@@ -55,7 +55,7 @@ dnl
 dnl See the "Since" comment for each macro you use to see what version
 dnl of the macros you require.
 m4_defun([PKG_PREREQ],
-[m4_define([PKG_MACROS_VERSION], [0.29.1])
+[m4_define([PKG_MACROS_VERSION], [0.29.2])
 m4_if(m4_version_compare(PKG_MACROS_VERSION, [$1]), -1,
     [m4_fatal([pkg.m4 version $1 or higher is required but ]PKG_MACROS_VERSION[ found])])
 ])dnl PKG_PREREQ
@@ -156,7 +156,7 @@ AC_ARG_VAR([$1][_CFLAGS], [C compiler flags for $1, overriding pkg-config])dnl
 AC_ARG_VAR([$1][_LIBS], [linker flags for $1, overriding pkg-config])dnl
 
 pkg_failed=no
-AC_MSG_CHECKING([for $1])
+AC_MSG_CHECKING([for $2])
 
 _PKG_CONFIG([$1][_CFLAGS], [cflags], [$2])
 _PKG_CONFIG([$1][_LIBS], [libs], [$2])
@@ -166,11 +166,11 @@ and $1[]_LIBS to avoid the need to call pkg-config.
 See the pkg-config man page for more details.])
 
 if test $pkg_failed = yes; then
-   	AC_MSG_RESULT([no])
+        AC_MSG_RESULT([no])
         _PKG_SHORT_ERRORS_SUPPORTED
         if test $_pkg_short_errors_supported = yes; then
 	        $1[]_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors --cflags --libs "$2" 2>&1`
-        else 
+        else
 	        $1[]_PKG_ERRORS=`$PKG_CONFIG --print-errors --cflags --libs "$2" 2>&1`
         fi
 	# Put the nasty error message in config.log where it belongs
@@ -187,7 +187,7 @@ installed software in a non-standard prefix.
 _PKG_TEXT])[]dnl
         ])
 elif test $pkg_failed = untried; then
-     	AC_MSG_RESULT([no])
+        AC_MSG_RESULT([no])
 	m4_default([$4], [AC_MSG_FAILURE(
 [The pkg-config script could not be found or is too old.  Make sure it
 is in your PATH or set the PKG_CONFIG environment variable to the full