When a header file is removed from generic-y (often accompanied by the addition of an arch specific header), the generated wrapper file will persist, and in some cases may still take precedence over the new arch header. For example commit f1fe2d21f4e1 ("MIPS: Add definitions for extended context") removed ucontext.h from generic-y in arch/mips/include/asm/, and added an arch/mips/include/uapi/asm/ucontext.h. The continued use of the wrapper when reusing a dirty build tree resulted in build failures in arch/mips/kernel/signal.c: arch/mips/kernel/signal.c: In function ‘sc_to_extcontext’: arch/mips/kernel/signal.c:142:12: error: ‘struct ucontext’ has no member named ‘uc_extcontext’ return &uc->uc_extcontext; ^ Fix by detecting and removing wrapper headers in generated header directories that do not correspond to a filename in generic-y, genhdr-y, or the newly introduced generated-y. Reported-by: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx> Reported-by: Hauke Mehrtens <hauke@xxxxxxxxxx> Reported-by: Heinrich Schuchardt <xypron.glpk@xxxxxx> Signed-off-by: James Hogan <james.hogan@xxxxxxxxxx> Acked-by: Arnd Bergmann <arnd@xxxxxxxx> Acked-by: Florian Fainelli <f.fainelli@xxxxxxxxx> Cc: Michal Marek <mmarek@xxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: Paul Burton <paul.burton@xxxxxxxxxx> Cc: Florian Fainelli <f.fainelli@xxxxxxxxx> Cc: linux-kbuild@xxxxxxxxxxxxxxx Cc: linux-arch@xxxxxxxxxxxxxxx Cc: linux-mips@xxxxxxxxxxxxxx --- Changes in v3: - Ensure FORCE actually gets marked .PHONY. Changes in v2: - Rewrite a bit, drawing inspiration from Makefile.headersinst. - Exclude genhdr-y and generated-y (thanks to kbuild test robot). --- scripts/Makefile.asm-generic | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/scripts/Makefile.asm-generic b/scripts/Makefile.asm-generic index 045e0098e962..e4d017d53819 100644 --- a/scripts/Makefile.asm-generic +++ b/scripts/Makefile.asm-generic @@ -13,11 +13,26 @@ include scripts/Kbuild.include # Create output directory if not already present _dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj)) +# Stale wrappers when the corresponding files are removed from generic-y +# need removing. +generated-y := $(generic-y) $(genhdr-y) $(generated-y) +all-files := $(patsubst %, $(obj)/%, $(generated-y)) +old-headers := $(wildcard $(obj)/*.h) +unwanted := $(filter-out $(all-files),$(old-headers)) + quiet_cmd_wrap = WRAP $@ cmd_wrap = echo "\#include <asm-generic/$*.h>" >$@ -all: $(patsubst %, $(obj)/%, $(generic-y)) +quiet_cmd_remove = REMOVE $(unwanted) +cmd_remove = rm -f $(unwanted) + +all: $(patsubst %, $(obj)/%, $(generic-y)) FORCE + $(if $(unwanted),$(call cmd,remove),) @: $(obj)/%.h: $(call cmd,wrap) + +PHONY += FORCE +.PHONY: $(PHONY) +FORCE: ; -- 2.4.10