From f77bf01425b11947eeb3b5b54685212c302741b8 Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Mon, 15 Oct 2007 22:25:06 +0200 Subject: [PATCH] kbuild: introduce ccflags-y, asflags-y and ldflags-y Introduce ccflags-y, asflags-y and ldflags-y so we soon can deprecate use of EXTRA_CFLAGS, EXTRA_AFLAGS and EXTRA_LDFLAGS. This patch does not touch any in-tree users - thats next round. Lets get this committed first and then fix the users of the soon to be deprecated variants next. The rationale behind this change is to introduce support for makefile fragments like: ccflags-$(CONFIG_WHATEVER_DEBUG) := -DDEBUG As a replacement for the uglier: ifeq ($(CONFIG_WHATEVER_DEBUG),y) EXTRA_CFLAGS := -DDEBUG endif Signed-off-by: Sam Ravnborg --- Documentation/kbuild/makefiles.txt | 37 +++++++++++++++--------------- scripts/Makefile.build | 4 ++++ scripts/Makefile.lib | 16 +++++++++---- scripts/makelst | 4 ++-- 4 files changed, 35 insertions(+), 26 deletions(-) diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index 08fbe6cd309..f099b814d38 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt @@ -276,40 +276,39 @@ more details, with real examples. --- 3.7 Compilation flags - EXTRA_CFLAGS, EXTRA_AFLAGS, EXTRA_LDFLAGS + ccflags-y, asflags-y and ldflags-y + The three flags listed above applies only to the kbuild makefile + where they are assigned. They are used for all the normal + cc, as and ld invocation happenign during a recursive build. + Note: Flags with the same behaviour were previously named: + EXTRA_CFLAGS, EXTRA_AFLAGS and EXTRA_LDFLAGS. + They are yet supported but their use are deprecated. - All the EXTRA_ variables apply only to the kbuild makefile - where they are assigned. The EXTRA_ variables apply to all - commands executed in the kbuild makefile. - - $(EXTRA_CFLAGS) specifies options for compiling C files with - $(CC). + ccflags-y specifies options for compiling C files with $(CC). Example: # drivers/sound/emu10k1/Makefile - EXTRA_CFLAGS += -I$(obj) - ifdef DEBUG - EXTRA_CFLAGS += -DEMU10K1_DEBUG - endif + ccflags-y += -I$(obj) + ccflags-$(DEBUG) += -DEMU10K1_DEBUG This variable is necessary because the top Makefile owns the variable $(KBUILD_CFLAGS) and uses it for compilation flags for the entire tree. - $(EXTRA_AFLAGS) is a similar string for per-directory options + asflags-y is a similar string for per-directory options when compiling assembly language source. Example: #arch/x86_64/kernel/Makefile - EXTRA_AFLAGS := -traditional + asflags-y := -traditional - $(EXTRA_LDFLAGS) is a string for per-directory options to $(LD). + ldflags-y is a string for per-directory options to $(LD). Example: #arch/m68k/fpsp040/Makefile - EXTRA_LDFLAGS := -x + ldflags-y := -x CFLAGS_$@, AFLAGS_$@ @@ -495,9 +494,9 @@ more details, with real examples. Example: #fs/reiserfs/Makefile - EXTRA_CFLAGS := $(call cc-ifversion, -lt, 0402, -O1) + ccflags-y := $(call cc-ifversion, -lt, 0402, -O1) - In this example, EXTRA_CFLAGS will be assigned the value -O1 if the + In this example, ccflags-y will be assigned the value -O1 if the $(CC) version is less than 4.2. cc-ifversion takes all the shell operators: -eq, -ne, -lt, -le, -gt, and -ge @@ -783,7 +782,7 @@ When kbuild executes, the following steps are followed (roughly): Example: #arch/s390/Makefile LDFLAGS := -m elf_s390 - Note: EXTRA_LDFLAGS can be used to further customise + Note: ldflags-y can be used to further customise the flags used. See chapter 3.7. LDFLAGS_MODULE Options for $(LD) when linking modules @@ -1100,7 +1099,7 @@ When kbuild executes, the following steps are followed (roughly): When building the *.lds target, kbuild uses the variables: KBUILD_CPPFLAGS : Set in top-level Makefile - EXTRA_CPPFLAGS : May be set in the kbuild makefile + cppflags-y : May be set in the kbuild makefile CPPFLAGS_$(@F) : Target specific flags. Note that the full filename is used in this assignment. diff --git a/scripts/Makefile.build b/scripts/Makefile.build index d32b40048f1..de9836eee8b 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -22,6 +22,10 @@ EXTRA_AFLAGS := EXTRA_CFLAGS := EXTRA_CPPFLAGS := EXTRA_LDFLAGS := +asflags-y := +ccflags-y := +cppflags-y := +ldflags-y := # Read .config if it exist, otherwise ignore -include include/config/auto.conf diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 95e6e0fbdbd..3c5e88bfecf 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -1,3 +1,9 @@ +# Backward compatibility +asflags-y += $(EXTRA_AFLAGS) +ccflags-y += $(EXTRA_CFLAGS) +cppflags-y += $(EXTRA_CPPFLAGS) +ldflags-y += $(EXTRA_LDFLAGS) + # Figure out what we need to build from the various variables # =========================================================================== @@ -84,9 +90,9 @@ basename_flags = -D"KBUILD_BASENAME=KBUILD_STR($(call name-fix,$(basetarget)))" modname_flags = $(if $(filter 1,$(words $(modname))),\ -D"KBUILD_MODNAME=KBUILD_STR($(call name-fix,$(modname)))") -_c_flags = $(KBUILD_CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$(basetarget).o) -_a_flags = $(KBUILD_AFLAGS) $(EXTRA_AFLAGS) $(AFLAGS_$(basetarget).o) -_cpp_flags = $(KBUILD_CPPFLAGS) $(EXTRA_CPPFLAGS) $(CPPFLAGS_$(@F)) +_c_flags = $(KBUILD_CFLAGS) $(ccflags-y) $(CFLAGS_$(basetarget).o) +_a_flags = $(KBUILD_AFLAGS) $(asflags-y) $(AFLAGS_$(basetarget).o) +_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F)) # If building the kernel in a separate objtree expand all occurrences # of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/'). @@ -115,7 +121,7 @@ a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(KBUILD_CPPFLAGS) \ cpp_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(__cpp_flags) -ld_flags = $(LDFLAGS) $(EXTRA_LDFLAGS) +ld_flags = $(LDFLAGS) $(ldflags-y) # Finds the multi-part object the current object will be linked into modname-multi = $(sort $(foreach m,$(multi-used),\ @@ -145,7 +151,7 @@ $(obj)/%:: $(src)/%_shipped # --------------------------------------------------------------------------- quiet_cmd_ld = LD $@ -cmd_ld = $(LD) $(LDFLAGS) $(EXTRA_LDFLAGS) $(LDFLAGS_$(@F)) \ +cmd_ld = $(LD) $(LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F)) \ $(filter-out FORCE,$^) -o $@ # Objcopy diff --git a/scripts/makelst b/scripts/makelst index 4fc80f2b7e1..e6581496d82 100755 --- a/scripts/makelst +++ b/scripts/makelst @@ -3,8 +3,8 @@ # with correct relocations from System.map # Requires the following lines in makefile: #%.lst: %.c -# $(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$@) -g -c -o $*.o $< -# $(srctree)/scripts/makelst $*.o $(objtree)/System.map $(OBJDUMP) +# $(CC) $(c_flags) -g -c -o $*.o $< && +# $(srctree)/scripts/makelst $*.o System.map $(OBJDUMP) > $@ # # Copyright (C) 2000 IBM Corporation # Author(s): DJ Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com) -- 2.20.1