| Message ID | 1461952973-20054-1-git-send-email-patrickdepinguin@gmail.com |
|---|---|
| State | Changes Requested |
| Headers | show |
Hello, On Fri, 29 Apr 2016 20:02:53 +0200, Thomas De Schampheleire wrote: > To build host-ccache we need to call the bare compiler. With a standard > 'make', this is guaranteed because host-ccache is built as part of the > dependencies, and a target-specific variable sets HOSTCC/HOSTCXX to the > no-ccache version (see ). > However, this is not the case when using 'make host-ccache' explicitly > from a clean build. I think this means that the CC/CXX assignments in support/dependencies/dependencies.mk are useless, no? If you do "make clean host-tar", or "make clean host-xz" or "make clean host-sstrip", it will fail the same way, no? Doesn't this mean that those "special" package should be fixed to define CC=$(HOSTCC_NOCCACHE) CXX=$(HOSTCXX_NOCCACHE) in their environment ? > +# To build host-ccache we need to call the bare compiler. With a standard > +# 'make', this is guaranteed because host-ccache is built as part of the > +# dependencies, and a target-specific variable sets HOSTCC/HOSTCXX to the > +# no-ccache version (see support/dependencies/dependencies.mk). > +# However, this is not the case when using 'make host-ccache'. > +HOST_CCACHE_CONF_ENV += CC=$(HOSTCC_NOCCACHE) CXX=$(HOSTCXX_NOCCACHE) Double quotes around the variable value? Thanks, Thomas
Hi Thomas, On Sun, May 1, 2016 at 2:39 PM, Thomas Petazzoni <thomas.petazzoni@free-electrons.com> wrote: > Hello, > > On Fri, 29 Apr 2016 20:02:53 +0200, Thomas De Schampheleire wrote: > >> To build host-ccache we need to call the bare compiler. With a standard >> 'make', this is guaranteed because host-ccache is built as part of the >> dependencies, and a target-specific variable sets HOSTCC/HOSTCXX to the >> no-ccache version (see ).fo >> However, this is not the case when using 'make host-ccache' explicitly >> from a clean build. > > I think this means that the CC/CXX assignments in > support/dependencies/dependencies.mk are useless, no? If you do "make > clean host-tar", or "make clean host-xz" or "make clean host-sstrip", > it will fail the same way, no? Doesn't this mean that those "special" > package should be fixed to define CC=$(HOSTCC_NOCCACHE) > CXX=$(HOSTCXX_NOCCACHE) in their environment ? After some quick checking, it seems to depend which packages are in DEPENDENCIES_HOST_PREREQ: 'make clean host-foo' will fail if host-foo is in DEPENDENCIES_HOST_PREREQ but will succeed if it is not. This is because packages that all packages get 'dependencies' as dependency, except packages that are itself in DEPENDENCIES_HOST_PREREQ. So, on my system, 'make clean host-xz' worked fine because I have a suitable xzcat already and hence host-xz is not put in DEPENDENCIES_HOST_PREREQ. Similar for host-tar. If I cheat and add host-xz in DEPENDENCIES_HOST_PREREQ unconditionally, 'make clean host-xz' indeed fails. This difference depending on the host system also means that a solution where e.g. host-xz is changed to set CC and CXX to no-ccache-versions is suboptimal: in case host-xz is not in DEPENDENCIES_HOST_PREREQ, the package would be built without ccache even if it were available. One could argue that there's no need to build host-xz in this scenario, but I can imagine other packages that can be mandatory in some situations and optional in others. Maybe this is nothing to worry about and we should keep things simple: don't use ccache for host packages that are potentially a core dependency for buildroot. What are your thoughts? > >> +# To build host-ccache we need to call the bare compiler. With a standard >> +# 'make', this is guaranteed because host-ccache is built as part of the >> +# dependencies, and a target-specific variable sets HOSTCC/HOSTCXX to the >> +# no-ccache version (see support/dependencies/dependencies.mk). >> +# However, this is not the case when using 'make host-ccache'. >> +HOST_CCACHE_CONF_ENV += CC=$(HOSTCC_NOCCACHE) CXX=$(HOSTCXX_NOCCACHE) > > Double quotes around the variable value? Yes, indeed. Need to fix that in any case. /Thomas
Hello, On Sun, 1 May 2016 22:11:18 +0200, Thomas De Schampheleire wrote: > > I think this means that the CC/CXX assignments in > > support/dependencies/dependencies.mk are useless, no? If you do "make > > clean host-tar", or "make clean host-xz" or "make clean host-sstrip", > > it will fail the same way, no? Doesn't this mean that those "special" > > package should be fixed to define CC=$(HOSTCC_NOCCACHE) > > CXX=$(HOSTCXX_NOCCACHE) in their environment ? > > After some quick checking, it seems to depend which packages are in > DEPENDENCIES_HOST_PREREQ: 'make clean host-foo' will fail if host-foo > is in DEPENDENCIES_HOST_PREREQ but will succeed if it is not. This is > because packages that all packages get 'dependencies' as dependency, > except packages that are itself in DEPENDENCIES_HOST_PREREQ. > > So, on my system, 'make clean host-xz' worked fine because I have a > suitable xzcat already and hence host-xz is not put in > DEPENDENCIES_HOST_PREREQ. Similar for host-tar. If I cheat and add > host-xz in DEPENDENCIES_HOST_PREREQ unconditionally, 'make clean > host-xz' indeed fails. > > This difference depending on the host system also means that a > solution where e.g. host-xz is changed to set CC and CXX to > no-ccache-versions is suboptimal: in case host-xz is not in > DEPENDENCIES_HOST_PREREQ, the package would be built without ccache > even if it were available. One could argue that there's no need to > build host-xz in this scenario, but I can imagine other packages that > can be mandatory in some situations and optional in others. > Maybe this is nothing to worry about and we should keep things simple: > don't use ccache for host packages that are potentially a core > dependency for buildroot. > > What are your thoughts? I think we should be simple, and indeed build those few packages always without ccache. I don't think we have any package that depends on "host-tar". Regarding host-xz, I'm not that sure, but it's a small package, so building it without ccache is not a big deal. Alternatively, we could try to make those packages depend on host-ccache. But I'm really not sure it's worth it. Thanks! Thomas
diff --git a/package/ccache/ccache.mk b/package/ccache/ccache.mk index c4f0310..ae369a6 100644 --- a/package/ccache/ccache.mk +++ b/package/ccache/ccache.mk @@ -21,6 +21,13 @@ CCACHE_LICENSE_FILES = LICENSE.txt GPL-3.0.txt # has zero dependency besides the C library. HOST_CCACHE_CONF_OPTS += --with-bundled-zlib +# To build host-ccache we need to call the bare compiler. With a standard +# 'make', this is guaranteed because host-ccache is built as part of the +# dependencies, and a target-specific variable sets HOSTCC/HOSTCXX to the +# no-ccache version (see support/dependencies/dependencies.mk). +# However, this is not the case when using 'make host-ccache'. +HOST_CCACHE_CONF_ENV += CC=$(HOSTCC_NOCCACHE) CXX=$(HOSTCXX_NOCCACHE) + # Patch host-ccache as follows: # - Use BR_CACHE_DIR instead of CCACHE_DIR, because CCACHE_DIR # is already used by autotargets for the ccache package.