In this v2 I just added an unconditional -Wno-pedantic and omitted the
change to spew error on STDERR. This more narrowly fixes the immediate
issue and doesn't get into whether we should use /dev/null or whatever
as input.
I then noticed that the same bug was present in
"GENERATE_COMPILATION_DATABASE=yes", so there's now a 2nd patch to fix
that.
Ævar Arnfjörð Bjarmason (2):
Makefile: make COMPUTE_HEADER_DEPENDENCIES=auto work with
DEVOPTS=pedantic
Makefile: pass -Wno-pendantic under GENERATE_COMPILATION_DATABASE=yes
Makefile | 2 ++
1 file changed, 2 insertions(+)
Range-diff against v1:
1: 3ff8ea12bf3 ! 1: 31c871e9bf6 Makefile: make COMPUTE_HEADER_DEPENDENCIES=auto work with DEVOPTS=pedantic
@@ Commit message
Makefile: make COMPUTE_HEADER_DEPENDENCIES=auto work with DEVOPTS=pedantic
The "COMPUTE_HEADER_DEPENDENCIES" feature added in [1] was extended to
- use auto-detection in [2]. Then when -Wpedantic support was added to
- DEVOPTS in [3] we started passing -Wpedantic in combination with
- -Werror to the compiler here.
+ use auto-detection in [2], that "auto" detection has always piped
+ STDERR to /dev/null, so any failures on compilers that didn't support
+ these GCC flags would silently fall back to
+ "COMPUTE_HEADER_DEPENDENCIES=no".
- This broke the auto-detection, but since we'd quieted it in [4] we
- didn't find out. It was emitting all of this on STDERR under GCC:
+ Later when -Wpedantic support was added to DEVOPTS in [3] we started
+ passing -Wpedantic in combination with -Werror to the compiler
+ here. Note (to the pedantic): [3] actually passed "-pedantic", but it
+ and "-Wpedantic" are synonyms.
+
+ Turning on -Wpedantic in [3] broke the auto-detection, since this
+ relies on compiling an empty program. GCC would loudly complain on
+ STDERR:
/dev/null:1: error: ISO C forbids an empty translation unit
[-Werror=pedantic]
@@ Commit message
earlier diagnostics
cc1: all warnings being treated as errors
- Let's fix that bug by maintaining a NON_DEVELOPER_CFLAGS, it's like
- ALL_CFLAGS but without anything we add in config.mak.dev, and
- furthermore stop redirecting STDERR to /dev/null, this means that
- someone whose compiler doesn't support this will see this output, but
- also this new message:
+ But as that ended up in the "$(dep_check)" variable due to the "2>&1"
+ in [2] we didn't see it.
- Non-zero 1 exit with COMPUTE_HEADER_DEPENDENCIES=auto, set it to "yes" or "no" to quiet auto-detect
+ Then when [4] made DEVOPTS=pedantic the default specifying
+ "DEVELOPER=1" would effectively set "COMPUTE_HEADER_DEPENDENCIES=no".
+
+ To fix these issues let's unconditionally pass -Wno-pedantic after
+ $(ALL_CFLAGS), we might get a -Wpedantic via config.mak.dev after, or
+ the builder might specify it via CFLAGS. In either case this will undo
+ current and future problems with -Wpedantic.
- It's also possible that some compilers will emit warnings but still
- give a zero exit code, anyone using a compiler like that will
- potentially get more verbose output from the Makefile until they set
- COMPUTE_HEADER_DEPENDENCIES=no. E.g. on AIX's xlc we'll now emit:
+ I think it would make sense to simply remove the "2>&1", it would mean
+ that anyone using a non-GCC-like compiler would get warnings under
+ COMPUTE_HEADER_DEPENDENCIES=auto, e.g on AIX's xlc would emit:
/opt/IBM/xlc/13.1.3/bin/.orig/xlc: 1501-208 (S) command option D is missing a subargument
Non-zero 40 exit with COMPUTE_HEADER_DEPENDENCIES=auto, set it to "yes" or "no" to quiet auto-detect
@@ Commit message
cc: refused to overwrite input file by output file: /dev/null
Non-zero 1 exit with COMPUTE_HEADER_DEPENDENCIES=auto, set it to "yes" or "no" to quiet auto-detect
- Both are quieted by setting COMPUTE_HEADER_DEPENDENCIES=no as
- suggested.
-
- I considered piping the output and the exit code to a variable
- instead, but e.g. under GCC that would lose the coloring in the error
- messages.
+ Both could be quieted by setting COMPUTE_HEADER_DEPENDENCIES=no
+ explicitly, as suggested, but let's see if this'll fix it without
+ emitting too much noise at those that aren't using "gcc" or "clang".
1. f2fabbf76e4 (Teach Makefile to check header dependencies,
2010-01-26)
@@ Commit message
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx>
## Makefile ##
-@@ Makefile: ALL_COMMANDS_TO_INSTALL += git-upload-archive$(X)
- ALL_COMMANDS_TO_INSTALL += git-upload-pack$(X)
- endif
-
--ALL_CFLAGS = $(DEVELOPER_CFLAGS) $(CPPFLAGS) $(CFLAGS)
-+NON_DEVELOPER_CFLAGS = $(CPPFLAGS) $(CFLAGS)
-+ALL_CFLAGS = $(DEVELOPER_CFLAGS) $(NON_DEVELOPER_CFLAGS)
- ALL_LDFLAGS = $(LDFLAGS)
-
- comma := ,
-@@ Makefile: COMPUTE_HEADER_DEPENDENCIES = auto
- endif
+@@ Makefile: endif
ifeq ($(COMPUTE_HEADER_DEPENDENCIES),auto)
--dep_check = $(shell $(CC) $(ALL_CFLAGS) \
-+dep_check = $(shell $(CC) $(NON_DEVELOPER_CFLAGS) \
+ dep_check = $(shell $(CC) $(ALL_CFLAGS) \
++ -Wno-pedantic \
-c -MF /dev/null -MQ /dev/null -MMD -MP \
-- -x c /dev/null -o /dev/null 2>&1; \
-+ -x c /dev/null -o /dev/null; \
+ -x c /dev/null -o /dev/null 2>&1; \
echo $$?)
- ifeq ($(dep_check),0)
- override COMPUTE_HEADER_DEPENDENCIES = yes
- else
-+$(info Non-zero $(dep_check) exit with COMPUTE_HEADER_DEPENDENCIES=auto, set it to "yes" or "no" to quiet auto-detect)
- override COMPUTE_HEADER_DEPENDENCIES = no
- endif
- endif
-: ----------- > 2: 6b18bd08894 Makefile: pass -Wno-pendantic under GENERATE_COMPILATION_DATABASE=yes
--
2.33.0.1225.g9f062250122
