diff --git a/Makefile b/Makefile
index 891866af0787..ce5a297ecd7c 100644
--- a/Makefile
+++ b/Makefile
@@ -669,9 +669,10 @@ endif # KBUILD_EXTMOD
 # Defaults to vmlinux, but the arch makefile usually adds further targets
 all: vmlinux
 
-CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage \
-	$(call cc-option,-fno-tree-loop-im) \
-	$(call cc-disable-warning,maybe-uninitialized,)
+CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
+ifdef CONFIG_CC_IS_GCC
+CFLAGS_GCOV	+= -fno-tree-loop-im
+endif
 export CFLAGS_GCOV
 
 # The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
@@ -679,12 +680,14 @@ ifdef CONFIG_FUNCTION_TRACER
   CC_FLAGS_FTRACE := -pg
 endif
 
-RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
-RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
-RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
-RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
-RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
-RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
+ifdef CONFIG_CC_IS_GCC
+RETPOLINE_CFLAGS	:= $(call cc-option,-mindirect-branch=thunk-extern -mindirect-branch-register)
+RETPOLINE_VDSO_CFLAGS	:= $(call cc-option,-mindirect-branch=thunk-inline -mindirect-branch-register)
+endif
+ifdef CONFIG_CC_IS_CLANG
+RETPOLINE_CFLAGS	:= -mretpoline-external-thunk
+RETPOLINE_VDSO_CFLAGS	:= -mretpoline
+endif
 export RETPOLINE_CFLAGS
 export RETPOLINE_VDSO_CFLAGS
 
@@ -737,7 +740,7 @@ include/config/auto.conf:
 endif # may-sync-config
 endif # need-config
 
-KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
+KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
 KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
 KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
 KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
@@ -752,17 +755,19 @@ KBUILD_CFLAGS += -Os
 endif
 
 # Tell gcc to never replace conditional load with a non-conditional one
+ifdef CONFIG_CC_IS_GCC
+# gcc-10 renamed --param=allow-store-data-races=0 to
+# -fno-allow-store-data-races.
 KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
 KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
+endif
 
 ifdef CONFIG_READABLE_ASM
 # Disable optimizations that make assembler listings hard to read.
 # reorder blocks reorders the control in the function
 # ipa clone creates specialized cloned functions
 # partial inlining inlines only parts of functions
-KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
-                 $(call cc-option,-fno-ipa-cp-clone,) \
-                 $(call cc-option,-fno-partial-inlining)
+KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
 endif
 
 ifneq ($(CONFIG_FRAME_WARN),0)
@@ -854,8 +859,10 @@ DEBUG_CFLAGS	+= -gdwarf-$(dwarf-version-y)
 endif
 
 ifdef CONFIG_DEBUG_INFO_REDUCED
-DEBUG_CFLAGS	+= $(call cc-option, -femit-struct-debug-baseonly) \
-		   $(call cc-option,-fno-var-tracking)
+DEBUG_CFLAGS	+= -fno-var-tracking
+ifdef CONFIG_CC_IS_GCC
+DEBUG_CFLAGS	+= -femit-struct-debug-baseonly
+endif
 endif
 
 ifdef CONFIG_DEBUG_INFO_COMPRESSED
@@ -889,6 +896,7 @@ ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
   endif
 endif
 ifdef CONFIG_HAVE_FENTRY
+  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
   ifeq ($(call cc-option-yn, -mfentry),y)
     CC_FLAGS_FTRACE	+= -mfentry
     CC_FLAGS_USING	+= -DCC_USING_FENTRY
@@ -901,7 +909,7 @@ endif
 
 # We trigger additional mismatches with less inlining
 ifdef CONFIG_DEBUG_SECTION_MISMATCH
-KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
+KBUILD_CFLAGS += -fno-inline-functions-called-once
 endif
 
 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
@@ -980,14 +988,16 @@ KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
 
 # We'll want to enable this eventually, but it's not going away for 5.7 at least
 KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
-KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
+KBUILD_CFLAGS += -Wno-array-bounds
 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
 
 # Another good warning that we'll want to enable eventually
 KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
 
 # Enabled with W=2, disabled by default as noisy
-KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
+ifdef CONFIG_CC_IS_GCC
+KBUILD_CFLAGS += -Wno-maybe-uninitialized
+endif
 
 # disable invalid "can't wrap" optimizations for signed / pointers
 KBUILD_CFLAGS	+= -fno-strict-overflow
@@ -996,7 +1006,9 @@ KBUILD_CFLAGS	+= -fno-strict-overflow
 KBUILD_CFLAGS  += -fno-stack-check
 
 # conserve stack if available
-KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
+ifdef CONFIG_CC_IS_GCC
+KBUILD_CFLAGS   += -fconserve-stack
+endif
 
 # Prohibit date/time macros, which would make the build non-deterministic
 KBUILD_CFLAGS   += -Werror=date-time
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 5ddd575159fb..7d3d29203a72 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -365,6 +365,7 @@ config STRIP_ASM_SYMS
 config READABLE_ASM
 	bool "Generate readable assembler code"
 	depends on DEBUG_KERNEL
+	depends on CC_IS_GCC
 	help
 	  Disable some compiler optimizations that tend to generate human unreadable
 	  assembler output. This may make the kernel slightly slower, but it helps
@@ -383,6 +384,7 @@ config HEADERS_INSTALL
 
 config DEBUG_SECTION_MISMATCH
 	bool "Enable full Section mismatch analysis"
+	depends on CC_IS_GCC
 	help
 	  The section mismatch analysis checks if there are illegal
 	  references from one section to another section.