From 5fc10e76fa2a96d0207ed4d0cc9d16fb61371f71 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 27 Jun 2023 08:30:13 +0900 Subject: [PATCH] kbuild: revive "Entering directory" for Make >= 4.4.1 With commit 9da0763bdd82 ("kbuild: Use relative path when building in a subdir of the source tree"), compiler messages in out-of-tree builds include relative paths, which are relative to the build directory, not the directory where make was started. To help IDEs/editors find the source files, Kbuild lets GNU Make print "Entering directory ..." when it changes the working directory. It has been working fine for a long time, but David reported it is broken with the latest GNU Make. The behavior was changed by GNU Make commit 8f9e7722ff0f ("[SV 63537] Fix setting -w in makefiles"). Previously, setting --no-print-directory to MAKEFLAGS only affected child makes, but it is now interpreted in the current make as soon as it is set. [test code] $ cat /tmp/Makefile ifneq ($(SUBMAKE),1) MAKEFLAGS += --no-print-directory all: ; $(MAKE) SUBMAKE=1 else all: ; : endif [before 8f9e7722ff0f] $ make -C /tmp make: Entering directory '/tmp' make SUBMAKE=1 : make: Leaving directory '/tmp' [after 8f9e7722ff0f] $ make -C /tmp make SUBMAKE=1 : Previously, the effect of --no-print-directory was delayed until Kbuild started the directory descending, but it is no longer true with GNU Make 4.4.1. This commit adds one more recursion to cater to GNU Make >= 4.4.1. When Kbuild needs to change the working directory, __submake will be executed twice. __submake without --no-print-directory --> show "Entering directory ..." __submake with --no-print-directory --> parse the rest of Makefile We end up with one more recursion than needed for GNU Make < 4.4.1, but I do not want to complicate the version check. Reported-by: David Howells Closes: https://lore.kernel.org/all/2427604.1686237298@warthog.procyon.org.uk/ Signed-off-by: Masahiro Yamada Tested-by: Nicolas Schier --- Makefile | 36 ++++++++++++++++++++---------------- 1 file changed, 20 insertions(+), 16 deletions(-) diff --git a/Makefile b/Makefile index 70b314059d8b..7edb00603b7e 100644 --- a/Makefile +++ b/Makefile @@ -191,13 +191,6 @@ $(if $(abs_objtree),, \ abs_objtree := $(realpath $(abs_objtree)) endif # ifneq ($(KBUILD_OUTPUT),) -ifeq ($(abs_objtree),$(CURDIR)) -# Suppress "Entering directory ..." unless we are changing the work directory. -MAKEFLAGS += --no-print-directory -else -need-sub-make := 1 -endif - ifneq ($(words $(subst :, ,$(abs_srctree))), 1) $(error source directory cannot contain spaces or colons) endif @@ -212,6 +205,23 @@ endif export sub_make_done := 1 +endif # sub_make_done + +ifeq ($(abs_objtree),$(CURDIR)) +# Suppress "Entering directory ..." if we are at the final work directory. +no-print-directory := --no-print-directory +else +# Recursion to show "Entering directory ..." +need-sub-make := 1 +endif + +ifeq ($(filter --no-print-directory, $(MAKEFLAGS)),) +# If --no-print-directory is unset, recurse once again to set it. +# You may end up recursing into __sub-make twice. This is needed due to the +# behavior change in GNU Make 4.4.1. +need-sub-make := 1 +endif + ifeq ($(need-sub-make),1) PHONY += $(MAKECMDGOALS) __sub-make @@ -221,18 +231,12 @@ $(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make # Invoke a second make in the output directory, passing relevant variables __sub-make: - $(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS) + $(Q)$(MAKE) $(no-print-directory) -C $(abs_objtree) \ + -f $(abs_srctree)/Makefile $(MAKECMDGOALS) -endif # need-sub-make -endif # sub_make_done +else # need-sub-make # We process the rest of the Makefile if this is the final invocation of make -ifeq ($(need-sub-make),) - -# Do not print "Entering directory ...", -# but we want to display it when entering to the output directory -# so that IDEs/editors are able to understand relative filenames. -MAKEFLAGS += --no-print-directory ifeq ($(abs_srctree),$(abs_objtree)) # building in the source tree