| Message ID | 20181228104335.22379-5-thomas.petazzoni@bootlin.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Top-level parallel build support | expand |
Thomas, All, On 2018-12-28 11:43 +0100, Thomas Petazzoni spake thusly: > With per-package folder support, top-level parallel build becomes > safe, so we can enclose the .NOTPARALLEL statement in a > !BR2_PER_PACKAGE_DIRECTORIES condition. > > Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Regards, Yann E. MORIN. > --- > Makefile | 19 +++++-------------- > 1 file changed, 5 insertions(+), 14 deletions(-) > > diff --git a/Makefile b/Makefile > index e01ec4c963..74c0757fd8 100644 > --- a/Makefile > +++ b/Makefile > @@ -228,21 +228,12 @@ ifeq ($(filter $(noconfig_targets),$(MAKECMDGOALS)),) > -include $(BR2_CONFIG) > endif > > -# Parallel execution of this Makefile is disabled because it changes > -# the packages building order, that can be a problem for two reasons: > -# - If a package has an unspecified optional dependency and that > -# dependency is present when the package is built, it is used, > -# otherwise it isn't (but compilation happily proceeds) so the end > -# result will differ if the order is swapped due to parallel > -# building. > -# - Also changing the building order can be a problem if two packages > -# manipulate the same file in the target directory. > -# > -# Taking into account the above considerations, if you still want to execute > -# this top-level Makefile in parallel comment the ".NOTPARALLEL" line and > -# use the -j<jobs> option when building, e.g: > -# make -j$((`getconf _NPROCESSORS_ONLN`+1)) > +ifeq ($(BR2_PER_PACKAGE_DIRECTORIES),) > +# Disable top-level parallel build if per-package directories is not > +# used. Indeed, per-package directories is necessary to guarantee > +# determinism and reproducibility with top-level parallel build. > .NOTPARALLEL: > +endif > > # timezone and locale may affect build output > ifeq ($(BR2_REPRODUCIBLE),y) > -- > 2.20.1 >
diff --git a/Makefile b/Makefile index e01ec4c963..74c0757fd8 100644 --- a/Makefile +++ b/Makefile @@ -228,21 +228,12 @@ ifeq ($(filter $(noconfig_targets),$(MAKECMDGOALS)),) -include $(BR2_CONFIG) endif -# Parallel execution of this Makefile is disabled because it changes -# the packages building order, that can be a problem for two reasons: -# - If a package has an unspecified optional dependency and that -# dependency is present when the package is built, it is used, -# otherwise it isn't (but compilation happily proceeds) so the end -# result will differ if the order is swapped due to parallel -# building. -# - Also changing the building order can be a problem if two packages -# manipulate the same file in the target directory. -# -# Taking into account the above considerations, if you still want to execute -# this top-level Makefile in parallel comment the ".NOTPARALLEL" line and -# use the -j<jobs> option when building, e.g: -# make -j$((`getconf _NPROCESSORS_ONLN`+1)) +ifeq ($(BR2_PER_PACKAGE_DIRECTORIES),) +# Disable top-level parallel build if per-package directories is not +# used. Indeed, per-package directories is necessary to guarantee +# determinism and reproducibility with top-level parallel build. .NOTPARALLEL: +endif # timezone and locale may affect build output ifeq ($(BR2_REPRODUCIBLE),y)
With per-package folder support, top-level parallel build becomes safe, so we can enclose the .NOTPARALLEL statement in a !BR2_PER_PACKAGE_DIRECTORIES condition. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> --- Makefile | 19 +++++-------------- 1 file changed, 5 insertions(+), 14 deletions(-)