Re: [PATCH v2] travis-ci: enable more warnings on travis linux-gcc job
Jeff King writes: > Unfortunately I think that's hard to do in pure make. But we're already > relying on $(shell) here, so we could just move the logic there. > > Something like the patch below, perhaps. It should do the right thing on > clang and gcc, and I added in an extra clang-only warning I've found > useful. Otherwise the list of flags comes from your patch. I see this discussion is going in the right direction, and like the approach taken by this "how about this" patch. Thanks.
Re: [PATCH v2] travis-ci: enable more warnings on travis linux-gcc job
On Sat, Mar 17, 2018 at 12:08:32PM -0400, Jeff King wrote: > +case "$($CC --version 2>&1)" in > +gcc*) > + print_flags gcc > + ;; > +clang*) > + print_flags clang > + ;; > +*) > + : unknown compiler family > + ;; > +esac By the way, one annoying thing is that running "cc --version" when "cc" is actually "gcc" will print something like: cc (Debian 7.3.0-11) 7.3.0 even though it supports all of the gcc knobs. This means that: make DEVELOPER=1 without further config won't get these knobs, because we (rightly) default CC=cc. Probably this detection could be a bit more clever, like: cc*Free Software Foundation") print_flags gcc or something. I don't have any non-gcc/clang compilers to test with, so I'm not sure what they even print for "--version" (if anything). -Peff
Re: [PATCH v2] travis-ci: enable more warnings on travis linux-gcc job
On Sat, Mar 17, 2018 at 03:59:23PM +0100, Duy Nguyen wrote:
> On Sat, Mar 17, 2018 at 03:29:31PM +0100, Lars Schneider wrote:
> > I interpreted Peff's comment like this:
> >
> > If DEVELOPER=1 is set and we detect a gcc-6 in the makefile,
> > then we could set your additional flags in the makefile.
> >
> > This way every developer with a new compiler would run these
> > flags locally (if DEVELOPER=1 is set).
>
> Aha. Something like this? I split developer cflags out to a separate
> file because I imagine people may start to add gcc7, clang
Yeah, gcc 7 is already standard on debian unstable, so...
> +GCC_VER := $(shell sh -c '$(CC) --version | grep ^gcc >/dev/null && $(CC)
> -dumpversion | cut -f 1 -d .')
> +
> +ifeq ($(GCC_VER),6)
...this probably needs to be "greater than or equal to".
Unfortunately I think that's hard to do in pure make. But we're already
relying on $(shell) here, so we could just move the logic there.
Something like the patch below, perhaps. It should do the right thing on
clang and gcc, and I added in an extra clang-only warning I've found
useful. Otherwise the list of flags comes from your patch.
The "clang4" limit is just what I happened to have on my system to test
with. Some of those flags might work for clang3, and some of the
gcc6-only flags might work on newer versions of clang.
I was puzzled by -Wno-maybe-uninitialized, though. I think that has
found bugs for us before (but also false positives, but we usually
squelch those in the code). And it's part of -Wall, not -Wextra, so we
shouldn't need it as part of this patch, should we?
diff --git a/Makefile b/Makefile
index a1d8775adb..9dfd152a1e 100644
--- a/Makefile
+++ b/Makefile
@@ -442,15 +442,6 @@ GIT-VERSION-FILE: FORCE
# CFLAGS and LDFLAGS are for the users to override from the command line.
CFLAGS = -g -O2 -Wall
-DEVELOPER_CFLAGS = -Werror \
- -Wdeclaration-after-statement \
- -Wno-format-zero-length \
- -Wold-style-definition \
- -Woverflow \
- -Wpointer-arith \
- -Wstrict-prototypes \
- -Wunused \
- -Wvla
LDFLAGS =
ALL_CFLAGS = $(CPPFLAGS) $(CFLAGS)
ALL_LDFLAGS = $(LDFLAGS)
@@ -1051,7 +1042,7 @@ include config.mak.uname
-include config.mak
ifdef DEVELOPER
-CFLAGS += $(DEVELOPER_CFLAGS)
+include config.mak.dev
endif
comma := ,
diff --git a/config.mak.dev b/config.mak.dev
new file mode 100644
index 00..59aef342c4
--- /dev/null
+++ b/config.mak.dev
@@ -0,0 +1,28 @@
+CFLAGS += -Werror
+CFLAGS += -Wdeclaration-after-statement
+CFLAGS += -Wno-format-zero-length
+CFLAGS += -Wold-style-definition
+CFLAGS += -Woverflow
+CFLAGS += -Wpointer-arith
+CFLAGS += -Wstrict-prototypes
+CFLAGS += -Wunused
+CFLAGS += -Wvla
+
+COMPILER_FEATURES := $(shell ./detect-compiler $(CC))
+
+ifneq ($(filter clang4,$(COMPILER_FEATURES)),)
+CFLAGS += -Wtautological-constant-out-of-range-compare
+endif
+
+ifneq ($(or $(filter gcc6,$(COMPILER_FEATURES)),$(filter
clang4,$(COMPILER_FEATURES))),)
+CFLAGS += -Wextra
+CFLAGS += -Wmissing-prototypes
+CFLAGS += -Wno-empty-body
+CFLAGS += -Wno-missing-field-initializers
+CFLAGS += -Wno-sign-compare
+CFLAGS += -Wno-unused-function
+CFLAGS += -Wno-unused-parameter
+ifneq ($(filter gcc6,$(COMPILER_FEATURES)),)
+CFLAGS += -Wno-maybe-uninitialized
+endif
+endif
diff --git a/detect-compiler b/detect-compiler
new file mode 100755
index 00..043367828c
--- /dev/null
+++ b/detect-compiler
@@ -0,0 +1,32 @@
+#!/bin/sh
+#
+# Probe the compiler for vintage, version, etc. This is used for setting
+# optional make knobs under the DEVELOPER knob.
+
+CC="$*"
+
+print_flags() {
+ family=$1
+ version=$($CC -dumpversion | cut -f 1 -d .)
+
+ # Print a feature flag not only for the current version, but also
+ # for any prior versions we encompass. This avoids needing to do
+ # numeric comparisons in make, which are awkward.
+ while test "$version" -gt 0
+ do
+ echo $family$version
+ version=$((version - 1))
+ done
+}
+
+case "$($CC --version 2>&1)" in
+gcc*)
+ print_flags gcc
+ ;;
+clang*)
+ print_flags clang
+ ;;
+*)
+ : unknown compiler family
+ ;;
+esac
--
2.17.0.rc0.402.ged0b3fd1ee
Re: [PATCH v2] travis-ci: enable more warnings on travis linux-gcc job
On Sat, Mar 17, 2018 at 03:29:31PM +0100, Lars Schneider wrote: > >> Why isn't this just turning on DEVELOPER=1 if we know we have a capable > >> compiler? > > > > DEVELOPER=1 is always set even before this patch. It's set and > > exported in lib-travisci.sh. > > I interpreted Peff's comment like this: > > If DEVELOPER=1 is set and we detect a gcc-6 in the makefile, > then we could set your additional flags in the makefile. > > This way every developer with a new compiler would run these > flags locally (if DEVELOPER=1 is set). Actually, I was mostly just confused, and didn't realize that these were going above and beyond what's in DEVELOPER. But that said, now that I understand, I agree completely with your suggestion. :) -Peff
Re: [PATCH v2] travis-ci: enable more warnings on travis linux-gcc job
On Sat, Mar 17, 2018 at 03:29:31PM +0100, Lars Schneider wrote: > I interpreted Peff's comment like this: > > If DEVELOPER=1 is set and we detect a gcc-6 in the makefile, > then we could set your additional flags in the makefile. > > This way every developer with a new compiler would run these > flags locally (if DEVELOPER=1 is set). Aha. Something like this? I split developer cflags out to a separate file because I imagine people may start to add gcc7, clang -- 8< -- diff --git a/.travis.yml b/.travis.yml index 5f5ee4f3bd..0b3c50f5e7 100644 --- a/.travis.yml +++ b/.travis.yml @@ -16,10 +16,13 @@ compiler: addons: apt: +sources: +- ubuntu-toolchain-r-test packages: - language-pack-is - git-svn - apache2 +- gcc-6 matrix: include: diff --git a/Makefile b/Makefile index de4b8f0c02..e8321e44d6 100644 --- a/Makefile +++ b/Makefile @@ -436,15 +436,6 @@ GIT-VERSION-FILE: FORCE # CFLAGS and LDFLAGS are for the users to override from the command line. CFLAGS = -g -O2 -Wall -DEVELOPER_CFLAGS = -Werror \ - -Wdeclaration-after-statement \ - -Wno-format-zero-length \ - -Wold-style-definition \ - -Woverflow \ - -Wpointer-arith \ - -Wstrict-prototypes \ - -Wunused \ - -Wvla LDFLAGS = ALL_CFLAGS = $(CPPFLAGS) $(CFLAGS) ALL_LDFLAGS = $(LDFLAGS) @@ -1045,7 +1036,8 @@ include config.mak.uname -include config.mak ifdef DEVELOPER -CFLAGS += $(DEVELOPER_CFLAGS) +include config.mak.dev +CFLAGS += $(DEV_CFLAGS) endif comma := , diff --git a/config.mak.dev b/config.mak.dev index e69de29bb2..644d0d581f 100644 --- a/config.mak.dev +++ b/config.mak.dev @@ -0,0 +1,23 @@ +DEV_CFLAGS = +DEV_CFLAGS += -Werror +DEV_CFLAGS += -Wdeclaration-after-statement +DEV_CFLAGS += -Wno-format-zero-length +DEV_CFLAGS += -Wold-style-definition +DEV_CFLAGS += -Woverflow +DEV_CFLAGS += -Wpointer-arith +DEV_CFLAGS += -Wstrict-prototypes +DEV_CFLAGS += -Wunused +DEV_CFLAGS += -Wvla + +GCC_VER := $(shell sh -c '$(CC) --version | grep ^gcc >/dev/null && $(CC) -dumpversion | cut -f 1 -d .') + +ifeq ($(GCC_VER),6) +DEV_CFLAGS += -Wextra +DEV_CFLAGS += -Wmissing-prototypes +DEV_CFLAGS += -Wno-empty-body +DEV_CFLAGS += -Wno-maybe-uninitialized +DEV_CFLAGS += -Wno-missing-field-initializers +DEV_CFLAGS += -Wno-sign-compare +DEV_CFLAGS += -Wno-unused-function +DEV_CFLAGS += -Wno-unused-parameter +endif -- 8< --
Re: [PATCH v2] travis-ci: enable more warnings on travis linux-gcc job
> On 17 Mar 2018, at 09:01, Duy Nguyen wrote: > > On Fri, Mar 16, 2018 at 10:22 PM, Jeff King wrote: >>> diff --git a/ci/run-build-and-tests.sh b/ci/run-build-and-tests.sh >>> index 3735ce413f..f6f346c468 100755 >>> --- a/ci/run-build-and-tests.sh >>> +++ b/ci/run-build-and-tests.sh >>> @@ -7,6 +7,22 @@ >>> >>> ln -s "$cache_dir/.prove" t/.prove >>> >>> +if [ "$jobname" = linux-gcc ]; then >>> + gcc-6 --version >>> + cat >config.mak <<-EOF >>> + CC=gcc-6 >>> + CFLAGS = -g -O2 -Wall >>> + CFLAGS += -Wextra >>> + CFLAGS += -Wmissing-prototypes >>> + CFLAGS += -Wno-empty-body >>> + CFLAGS += -Wno-maybe-uninitialized >>> + CFLAGS += -Wno-missing-field-initializers >>> + CFLAGS += -Wno-sign-compare >>> + CFLAGS += -Wno-unused-function >>> + CFLAGS += -Wno-unused-parameter >>> + EOF >>> +fi >> >> Why isn't this just turning on DEVELOPER=1 if we know we have a capable >> compiler? > > DEVELOPER=1 is always set even before this patch. It's set and > exported in lib-travisci.sh. I interpreted Peff's comment like this: If DEVELOPER=1 is set and we detect a gcc-6 in the makefile, then we could set your additional flags in the makefile. This way every developer with a new compiler would run these flags locally (if DEVELOPER=1 is set). - Lars
Re: [PATCH v2] travis-ci: enable more warnings on travis linux-gcc job
On Fri, Mar 16, 2018 at 10:22 PM, Jeff King wrote: >> diff --git a/ci/run-build-and-tests.sh b/ci/run-build-and-tests.sh >> index 3735ce413f..f6f346c468 100755 >> --- a/ci/run-build-and-tests.sh >> +++ b/ci/run-build-and-tests.sh >> @@ -7,6 +7,22 @@ >> >> ln -s "$cache_dir/.prove" t/.prove >> >> +if [ "$jobname" = linux-gcc ]; then >> + gcc-6 --version >> + cat >config.mak <<-EOF >> + CC=gcc-6 >> + CFLAGS = -g -O2 -Wall >> + CFLAGS += -Wextra >> + CFLAGS += -Wmissing-prototypes >> + CFLAGS += -Wno-empty-body >> + CFLAGS += -Wno-maybe-uninitialized >> + CFLAGS += -Wno-missing-field-initializers >> + CFLAGS += -Wno-sign-compare >> + CFLAGS += -Wno-unused-function >> + CFLAGS += -Wno-unused-parameter >> + EOF >> +fi > > Why isn't this just turning on DEVELOPER=1 if we know we have a capable > compiler? DEVELOPER=1 is always set even before this patch. It's set and exported in lib-travisci.sh. -- Duy
Re: [PATCH v2] travis-ci: enable more warnings on travis linux-gcc job
On Fri, Mar 16, 2018 at 08:33:55PM +0100, Nguyễn Thái Ngọc Duy wrote: > We have DEVELOPER config to enable more warnings, but since we can't set > a fixed gcc version to all devs, that has to be a bit more conservative. > On travis, we know almost exact version to be used (bumped to 6.x for > more warnings), we could be more aggressive. Certainly it makes sense to dial up any static checks we can for the Travis environment, but... > diff --git a/ci/run-build-and-tests.sh b/ci/run-build-and-tests.sh > index 3735ce413f..f6f346c468 100755 > --- a/ci/run-build-and-tests.sh > +++ b/ci/run-build-and-tests.sh > @@ -7,6 +7,22 @@ > > ln -s "$cache_dir/.prove" t/.prove > > +if [ "$jobname" = linux-gcc ]; then > + gcc-6 --version > + cat >config.mak <<-EOF > + CC=gcc-6 > + CFLAGS = -g -O2 -Wall > + CFLAGS += -Wextra > + CFLAGS += -Wmissing-prototypes > + CFLAGS += -Wno-empty-body > + CFLAGS += -Wno-maybe-uninitialized > + CFLAGS += -Wno-missing-field-initializers > + CFLAGS += -Wno-sign-compare > + CFLAGS += -Wno-unused-function > + CFLAGS += -Wno-unused-parameter > + EOF > +fi Why isn't this just turning on DEVELOPER=1 if we know we have a capable compiler? -Peff
