Hi,
this is the second version of my patch series that modifies one of our
CI jobs to compile with `-Og`. We have noticed that it may surface more
warnings that we do not see with `-O2`, so this should help to find more
bugs up front.
Changes compared to v1:
- Instead of adapting the "pedantic" job, we now adapt
"linux-gcc-default" to compile with `-Og`. This is because that job
uses ubuntu:latest and thus a recent compiler, and there are other
jobs with ubuntu:latest that continue to compile with `-O2`. So this
is a strict improvement of coverage for diagnostics.
- Add a way to override the optimization level to our Makefile, as
suggested by Peff.
Patrick
Patrick Steinhardt (2):
ci: fix check for Ubuntu 20.04
ci: compile "linux-gcc-default" job with -Og
Makefile | 3 ++-
ci/lib.sh | 2 +-
ci/run-build-and-tests.sh | 9 +++++++++
3 files changed, 12 insertions(+), 2 deletions(-)
Range-diff against v1:
1: f91004a438 = 1: f91004a438 ci: fix check for Ubuntu 20.04
2: 351dec4a4d ! 2: bdf0e40a77 ci: let pedantic job compile with -Og
@@ Metadata
Author: Patrick Steinhardt <ps@xxxxxx>
## Commit message ##
- ci: let pedantic job compile with -Og
+ ci: compile "linux-gcc-default" job with -Og
We have recently noticed that our CI does not always notice variables
that may be used uninitialized. While it is expected that compiler
@@ Commit message
While we could adapt all jobs to compile with `-Og` now, that would
potentially mask other warnings that only get diagnosed with `-O2`.
- Instead, only adapt the "pedantic" job to compile with `-Og`.
+ Instead, adapt the "linux-gcc-default" job to compile with `-Og`. This
+ job is chosen because it uses the "ubuntu:latest" image and should thus
+ have a comparatively recent compiler toolchain, and because we have
+ other jobs that use "ubuntu:latest" so that we do not loose coverage for
+ warnings diagnosed only on `-O2` level.
+
+ To make it easier to set up the optimization level in our CI, add
+ support in our Makefile to specify the level via an environment
+ variable.
Signed-off-by: Patrick Steinhardt <ps@xxxxxx>
+ ## Makefile ##
+@@ Makefile: endif
+ # tweaked by config.* below as well as the command-line, both of
+ # which'll override these defaults.
+ # Older versions of GCC may require adding "-std=gnu99" at the end.
+-CFLAGS = -g -O2 -Wall
++O ?= 2
++CFLAGS = -g -O$(O) -Wall
+ LDFLAGS =
+ CC_LD_DYNPATH = -Wl,-rpath,
+ BASIC_CFLAGS = -I.
+
## ci/run-build-and-tests.sh ##
-@@ ci/run-build-and-tests.sh: pedantic)
- # Don't run the tests; we only care about whether Git can be
- # built.
- export DEVOPTS=pedantic
+@@ ci/run-build-and-tests.sh: esac
+ run_tests=t
+
+ case "$jobname" in
++linux-gcc-default)
+ # Warnings generated by compilers are unfortunately specific to the
+ # optimization level. With `-O0`, many warnings won't be shown at all,
+ # whereas the optimizations performed by our default optimization level
+ # `-O2` will mask others. We thus use `-Og` here just so that we have
+ # at least one job with a different optimization level so that we can
+ # overall surface more warnings.
-+ cat >config.mak <<-EOF
-+ export CFLAGS=-Og
-+ EOF
- run_tests=
++ export O=g
++ ;;
+ linux-gcc)
+ export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
;;
- esac
--
2.45.2.409.g7b0defb391.dirty
Attachment:
signature.asc
Description: PGP signature
