Remove GCC support from Make

Test: out/build-aosp_arm64.ninja is the same before/after
Test: build_test on downstream branches
Change-Id: If7f8c12f2f288b1e589689361f9457acae634882
diff --git a/core/config.mk b/core/config.mk
index 5c4136a..696e1ef 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -85,6 +85,33 @@
 $(KATI_obsolete_var PRODUCT_COMPATIBILITY_MATRIX_LEVEL_OVERRIDE,Set FCM Version in device manifest instead. See $(CHANGES_URL)#PRODUCT_COMPATIBILITY_MATRIX_LEVEL_OVERRIDE)
 $(KATI_obsolete_var USE_CLANG_PLATFORM_BUILD,Clang is the only supported Android compiler. See $(CHANGES_URL)#USE_CLANG_PLATFORM_BUILD)
 $(KATI_obsolete_var BUILD_DROIDDOC,Droiddoc is only supported in Soong. See details on build/soong/java/droiddoc.go)
+$(KATI_obsolete_var \
+  DEFAULT_GCC_CPP_STD_VERSION \
+  HOST_GLOBAL_CFLAGS 2ND_HOST_GLOBAL_CFLAGS \
+  HOST_GLOBAL_CONLYFLAGS 2ND_HOST_GLOBAL_CONLYFLAGS \
+  HOST_GLOBAL_CPPFLAGS 2ND_HOST_GLOBAL_CPPFLAGS \
+  HOST_GLOBAL_LDFLAGS 2ND_HOST_GLOBAL_LDFLAGS \
+  HOST_GLOBAL_LLDFLAGS 2ND_HOST_GLOBAL_LLDFLAGS \
+  HOST_CLANG_SUPPORTED 2ND_HOST_CLANG_SUPPORTED \
+  HOST_CC 2ND_HOST_CC \
+  HOST_CXX 2ND_HOST_CXX \
+  HOST_CROSS_GLOBAL_CFLAGS 2ND_HOST_CROSS_GLOBAL_CFLAGS \
+  HOST_CROSS_GLOBAL_CONLYFLAGS 2ND_HOST_CROSS_GLOBAL_CONLYFLAGS \
+  HOST_CROSS_GLOBAL_CPPFLAGS 2ND_HOST_CROSS_GLOBAL_CPPFLAGS \
+  HOST_CROSS_GLOBAL_LDFLAGS 2ND_HOST_CROSS_GLOBAL_LDFLAGS \
+  HOST_CROSS_GLOBAL_LLDFLAGS 2ND_HOST_CROSS_GLOBAL_LLDFLAGS \
+  HOST_CROSS_CLANG_SUPPORTED 2ND_HOST_CROSS_CLANG_SUPPORTED \
+  HOST_CROSS_CC 2ND_HOST_CROSS_CC \
+  HOST_CROSS_CXX 2ND_HOST_CROSS_CXX \
+  TARGET_GLOBAL_CFLAGS 2ND_TARGET_GLOBAL_CFLAGS \
+  TARGET_GLOBAL_CONLYFLAGS 2ND_TARGET_GLOBAL_CONLYFLAGS \
+  TARGET_GLOBAL_CPPFLAGS 2ND_TARGET_GLOBAL_CPPFLAGS \
+  TARGET_GLOBAL_LDFLAGS 2ND_TARGET_GLOBAL_LDFLAGS \
+  TARGET_GLOBAL_LLDFLAGS 2ND_TARGET_GLOBAL_LLDFLAGS \
+  TARGET_CLANG_SUPPORTED 2ND_TARGET_CLANG_SUPPORTED \
+  TARGET_CC 2ND_TARGET_CC \
+  TARGET_CXX 2ND_TARGET_CXX \
+  ,GCC support has been removed. Use Clang instead)
 
 # This is marked as obsolete in envsetup.mk after reading the BoardConfig.mk
 $(KATI_deprecate_export It is a global setting. See $(CHANGES_URL)#export_keyword)