2018-04-06 6:43 GMT+09:00 Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>: > On 2018-03-26 13:48, Masahiro Yamada wrote: >> 2018-03-26 8:09 GMT+09:00 Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>: >>> The latest official Make release is 4.2.1 from mid-2016, but the current >>> git release has this relevant note in the NEWS file: >>> >>> * WARNING: Backward-incompatibility! >>> Number signs (#) appearing inside a macro reference or function invocation >>> no longer introduce comments and should not be escaped with backslashes: >>> thus a call such as: >>> foo := $(shell echo '#') >>> is legal. Previously the number sign needed to be escaped, for example: >>> foo := $(shell echo '\#') >>> Now this latter will resolve to "\#". If you want to write makefiles >>> portable to both versions, assign the number sign to a variable: >>> C := \# >>> foo := $(shell echo '$C') >>> This was claimed to be fixed in 3.81, but wasn't, for some reason. >>> To detect this change search for 'nocomment' in the .FEATURES variable. >>> >>> Prepare for whatever future Make release contains that change by fixing >>> up the .cmd file escaping - without this, make always thinks the command >>> string has changed and hence rebuilds everything. >>> >>> Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx> >>> --- >>> So the previous patch made everything build, but building again >>> revealed that this central place very much also needed fixing. >>> >>> scripts/Kbuild.include | 3 ++- >>> 1 file changed, 2 insertions(+), 1 deletion(-) >>> >>> diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include >>> index 065324a8046f..7a926e4688f4 100644 >>> --- a/scripts/Kbuild.include >>> +++ b/scripts/Kbuild.include >>> @@ -10,6 +10,7 @@ space := $(empty) $(empty) >>> space_escape := _-_SPACE_-_ >>> right_paren := ) >>> left_paren := ( >>> +pound := \# >>> >>> ### >>> # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o >>> @@ -328,7 +329,7 @@ endif >>> # (needed for make) >>> # Replace >'< with >'\''< to be able to enclose the whole string in '...' >>> # (needed for the shell) >>> -make-cmd = $(call escsq,$(subst \#,\\\#,$(subst $$,$$$$,$(cmd_$(1))))) >>> +make-cmd = $(call escsq,$(subst $(pound),\\$(pound),$(subst $$,$$$$,$(cmd_$(1))))) >>> >> >> Thanks for the patch, but this changes the behavior. >> With '#' replaced with $(pound), '\\' does not escape anything, >> so it is treated as '\\'. >> >> >> The following keeps the current behavior: >> >> make-cmd = $(call escsq,$(subst $(pound),\$(pound),$(subst >> $$,$$$$,$(cmd_$(1))))) >> >> >> >> But, I think the following is an even better fix: >> >> make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst >> $$,$$$$,$(cmd_$(1))))) > > Makefile quoting has never been my strong suit. I actually thought I > tested my change by looking at some .o.cmd files containing \# before > and after, but I was fooled by tools/ containing and using their own > copy of make-cmd - so tools/build/Build.include will also need fixing. > > Yes, writing $(pound) to the .cmd file seems like the safest choice. Do > you want me to respin or can/will you do the patch(es) yourself? > Can you send v2 please? I will pick it up shortly. -- Best Regards Masahiro Yamada -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
