kconfig / kbuild: Re-sync with Linux 4.19

[oweals/u-boot.git] / Makefile

diff --git a/Makefile b/Makefile
index 90769792025c6579b9a81535b9af21e815a022a9..a12ac9b46631070fbed887dd3b857dee21b887a6 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -271,11 +271,17 @@ CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
          else if [ -x /bin/bash ]; then echo /bin/bash; \
          else echo sh; fi ; fi)
 
+HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
+HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
+HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
+
 HOSTCC       = cc
 HOSTCXX      = c++
-HOSTCFLAGS   = -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer \
-               $(if $(CONFIG_TOOLS_DEBUG),-g)
-HOSTCXXFLAGS = -O2
+KBUILD_HOSTCFLAGS   := -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer \
+               $(if $(CONFIG_TOOLS_DEBUG),-g) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
+KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
+KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
+KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 
 # With the move to GCC 6, we have implicitly upgraded our language
 # standard to GNU11 (see https://gcc.gnu.org/gcc-5/porting_to.html).
@@ -284,11 +290,11 @@ HOSTCXXFLAGS = -O2
 # these that our host tools are GNU11 (i.e. C11 w/ GNU extensions).
 CSTD_FLAG := -std=gnu11
 ifeq ($(HOSTOS),linux)
-HOSTCFLAGS += $(CSTD_FLAG)
+KBUILD_HOSTCFLAGS += $(CSTD_FLAG)
 endif
 
 ifeq ($(HOSTOS),cygwin)
-HOSTCFLAGS     += -ansi
+KBUILD_HOSTCFLAGS      += -ansi
 endif
 
 # Mac OS X / Darwin's C preprocessor is Apple specific.  It
@@ -315,17 +321,17 @@ os_x_after = $(shell if [ $(DARWIN_MAJOR_VERSION) -ge $(1) -a \
 
 # Snow Leopards build environment has no longer restrictions as described above
 HOSTCC       = $(call os_x_before, 10, 5, "cc", "gcc")
-HOSTCFLAGS  += $(call os_x_before, 10, 4, "-traditional-cpp")
-HOSTLDFLAGS += $(call os_x_before, 10, 5, "-multiply_defined suppress")
+KBUILD_HOSTCFLAGS  += $(call os_x_before, 10, 4, "-traditional-cpp")
+KBUILD_HOSTLDFLAGS += $(call os_x_before, 10, 5, "-multiply_defined suppress")
 
 # since Lion (10.7) ASLR is on by default, but we use linker generated lists
 # in some host tools which is a problem then ... so disable ASLR for these
 # tools
-HOSTLDFLAGS += $(call os_x_before, 10, 7, "", "-Xlinker -no_pie")
+KBUILD_HOSTLDFLAGS += $(call os_x_before, 10, 7, "", "-Xlinker -no_pie")
 
 # macOS Mojave (10.14.X) 
 # Undefined symbols for architecture x86_64: "_PyArg_ParseTuple"
-HOSTLDFLAGS += $(call os_x_after, 10, 14, "-lpython -dynamclib", "")
+KBUILD_HOSTLDFLAGS += $(call os_x_after, 10, 14, "-lpython -dynamclib", "")
 endif
 
 # Decide whether to build built-in, modular, or both.
@@ -417,6 +423,23 @@ KBUILD_CFLAGS   := -Wall -Wstrict-prototypes \
                   -fno-builtin -ffreestanding $(CSTD_FLAG)
 KBUILD_CFLAGS  += -fshort-wchar -fno-strict-aliasing
 KBUILD_AFLAGS   := -D__ASSEMBLY__
+KBUILD_LDFLAGS  :=
+
+ifeq ($(cc-name),clang)
+ifneq ($(CROSS_COMPILE),)
+CLANG_TARGET   := --target=$(notdir $(CROSS_COMPILE:%-=%))
+GCC_TOOLCHAIN_DIR := $(dir $(shell which $(LD)))
+CLANG_PREFIX   := --prefix=$(GCC_TOOLCHAIN_DIR)
+GCC_TOOLCHAIN  := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
+endif
+ifneq ($(GCC_TOOLCHAIN),)
+CLANG_GCC_TC   := --gcc-toolchain=$(GCC_TOOLCHAIN)
+endif
+KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX)
+KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX)
+KBUILD_CFLAGS += $(call cc-option, -no-integrated-as)
+KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
+endif
 
 # Don't generate position independent code
 KBUILD_CFLAGS  += $(call cc-option,-fno-PIE)
@@ -428,12 +451,12 @@ UBOOTVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SU
 
 export VERSION PATCHLEVEL SUBLEVEL UBOOTRELEASE UBOOTVERSION
 export ARCH CPU BOARD VENDOR SOC CPUDIR BOARDDIR
-export CONFIG_SHELL HOSTCC HOSTCFLAGS HOSTLDFLAGS CROSS_COMPILE AS LD CC
-export CPP AR NM LDR STRIP OBJCOPY OBJDUMP
+export CONFIG_SHELL HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
+export CPP AR NM LDR STRIP OBJCOPY OBJDUMP KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS
 export MAKE LEX YACC AWK PERL PYTHON PYTHON2 PYTHON3
-export HOSTCXX HOSTCXXFLAGS CHECK CHECKFLAGS DTC DTC_FLAGS
+export HOSTCXX KBUILD_HOSTCXXFLAGS CHECK CHECKFLAGS DTC DTC_FLAGS
 
-export KBUILD_CPPFLAGS NOSTDINC_FLAGS UBOOTINCLUDE OBJCOPYFLAGS LDFLAGS
+export KBUILD_CPPFLAGS NOSTDINC_FLAGS UBOOTINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
 export KBUILD_CFLAGS KBUILD_AFLAGS
 
 export CC_VERSION_TEXT := $(shell $(CC) --version | head -n 1)
@@ -657,6 +680,9 @@ endif
 KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector)
 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
 
+# disable stringop warnings in gcc 8+
+KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
+
 # change __FILE__ to the relative path from the srctree
 KBUILD_CFLAGS  += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
 
@@ -681,7 +707,19 @@ ifeq ($(cc-name),clang)
 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
+KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
+# Quiet clang warning: comparison of unsigned expression < 0 is always false
+KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
+# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
+# source of a reference will be _MergedGlobals and not on of the whitelisted names.
+# See modpost pattern 2
+KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
 KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
+else
+
+# These warnings generated too much noise in a regular build.
+# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
+KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
 endif
 
 # turn jbsr into jsr for m68k
@@ -1691,7 +1729,7 @@ ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(ARCH)/Makefile.postlink)
 # Rule to link u-boot
 # May be overridden by arch/$(ARCH)/config.mk
 quiet_cmd_u-boot__ ?= LD      $@
-      cmd_u-boot__ ?= $(LD) $(LDFLAGS) $(LDFLAGS_u-boot) -o $@ \
+      cmd_u-boot__ ?= $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_u-boot) -o $@ \
       -T u-boot.lds $(u-boot-init)                             \
       --start-group $(u-boot-main) --end-group                 \
       $(PLATFORM_LIBS) -Map u-boot.map;                        \