From 7bf179de5b2dfae54a6839eaf7caba44a888ee2e Mon Sep 17 00:00:00 2001 From: Kevin Locke Date: Mon, 6 Jun 2022 20:42:54 -0600 Subject: [PATCH] kbuild: avoid regex RS for POSIX awk In 22f26f21774f8 awk was added to deduplicate *.mod files. The awk invocation passes -v RS='( |\n)' to match a space or newline character as the record separator. Unfortunately, POSIX states[1] > If RS contains more than one character, the results are unspecified. Some implementations (such as the One True Awk[2] used by the BSDs) do not treat RS as a regular expression. When awk does not support regex RS, build failures such as the following are produced (first error using allmodconfig): CC [M] arch/x86/events/intel/uncore.o CC [M] arch/x86/events/intel/uncore_nhmex.o CC [M] arch/x86/events/intel/uncore_snb.o CC [M] arch/x86/events/intel/uncore_snbep.o CC [M] arch/x86/events/intel/uncore_discovery.o LD [M] arch/x86/events/intel/intel-uncore.o ld: cannot find uncore_nhmex.o: No such file or directory ld: cannot find uncore_snb.o: No such file or directory ld: cannot find uncore_snbep.o: No such file or directory ld: cannot find uncore_discovery.o: No such file or directory make[3]: *** [scripts/Makefile.build:422: arch/x86/events/intel/intel-uncore.o] Error 1 make[2]: *** [scripts/Makefile.build:487: arch/x86/events/intel] Error 2 make[1]: *** [scripts/Makefile.build:487: arch/x86/events] Error 2 make: *** [Makefile:1839: arch/x86] Error 2 To avoid this, use printf(1) to produce a newline between each object path, instead of the space produced by echo(1), so that the default RS can be used by awk. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/awk.html [2]: https://github.com/onetrueawk/awk Fixes: 22f26f21774f ("kbuild: get rid of duplication in *.mod files") Signed-off-by: Kevin Locke Signed-off-by: Masahiro Yamada --- scripts/Makefile.build | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 1f01ac65c0cd..cac070aee791 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -251,8 +251,8 @@ $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE # To make this rule robust against "Argument list too long" error, # ensure to add $(obj)/ prefix by a shell command. -cmd_mod = echo $(call real-search, $*.o, .o, -objs -y -m) | \ - $(AWK) -v RS='( |\n)' '!x[$$0]++ { print("$(obj)/"$$0) }' > $@ +cmd_mod = printf '%s\n' $(call real-search, $*.o, .o, -objs -y -m) | \ + $(AWK) '!x[$$0]++ { print("$(obj)/"$$0) }' > $@ $(obj)/%.mod: FORCE $(call if_changed,mod) -- 2.20.1