From b1992c3772e69a6fd0e3fc81cd4d2820c8b6eca0 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sat, 27 Apr 2024 23:55:02 +0900 Subject: kbuild: use $(src) instead of $(srctree)/$(src) for source directory Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for checked-in source files. It is merely a convention without any functional difference. In fact, $(obj) and $(src) are exactly the same, as defined in scripts/Makefile.build: src := $(obj) When the kernel is built in a separate output directory, $(src) does not accurately reflect the source directory location. While Kbuild resolves this discrepancy by specifying VPATH=$(srctree) to search for source files, it does not cover all cases. For example, when adding a header search path for local headers, -I$(srctree)/$(src) is typically passed to the compiler. This introduces inconsistency between upstream and downstream Makefiles because $(src) is used instead of $(srctree)/$(src) for the latter. To address this inconsistency, this commit changes the semantics of $(src) so that it always points to the directory in the source tree. Going forward, the variables used in Makefiles will have the following meanings: $(obj) - directory in the object tree $(src) - directory in the source tree (changed by this commit) $(objtree) - the top of the kernel object tree $(srctree) - the top of the kernel source tree Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced with $(src). Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier --- scripts/dtc/Makefile | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'scripts/dtc') diff --git a/scripts/dtc/Makefile b/scripts/dtc/Makefile index 4d32b9497da9..a18657072541 100644 --- a/scripts/dtc/Makefile +++ b/scripts/dtc/Makefile @@ -16,12 +16,12 @@ libfdt = $(addprefix libfdt/,$(libfdt-objs)) fdtoverlay-objs := $(libfdt) fdtoverlay.o util.o # Source files need to get at the userspace version of libfdt_env.h to compile -HOST_EXTRACFLAGS += -I $(srctree)/$(src)/libfdt +HOST_EXTRACFLAGS += -I $(src)/libfdt HOST_EXTRACFLAGS += -DNO_YAML # Generated files need one more search path to include headers in source tree -HOSTCFLAGS_dtc-lexer.lex.o := -I $(srctree)/$(src) -HOSTCFLAGS_dtc-parser.tab.o := -I $(srctree)/$(src) +HOSTCFLAGS_dtc-lexer.lex.o := -I $(src) +HOSTCFLAGS_dtc-parser.tab.o := -I $(src) # dependencies on generated files need to be listed explicitly $(obj)/dtc-lexer.lex.o: $(obj)/dtc-parser.tab.h -- cgit v1.2.3