To solve the issue of carrying object files from previous builds,
Matias changed the archiving process to re-archive libapps.a on every compilation,
if libapps.a carries more object files, incremental compilation will waste too
many time in re-archiving, compared with the previous implement, this is a degradation
of the build system. Referring to mature engineering projects such as cmake, if there
is configuration or source file changed, the best solution should be to reconfigure
the environment.
Revert this PR to ensure the compilation speed during incremental compilation.
| commit 18137c0fec
| Author: Matias N <matias@protobits.dev>
| Date: Sat Sep 12 00:36:23 2020 -0300
|
| Fix: ensure archive files do not carry object files from prior builds
|
| This is the corresponding change to the one on main NuttX repo. In this
| case this involves splitting the build of libapps.a into: a) building
| all applications (which is safely parallelizable), b) adding each
| application's object files to the archive in turns (serial by nature).
|
| This removes the need for the flock used to protect the parallel build.
Testing:
sim:nsh
-------------------------------
| Patched | Current
-------------------------------
|$ time make | $ time make
|real 0m1.270s | real 0m1.728s
|user 0m0.971s | user 0m1.276s
|sys 0m0.363s | sys 0m0.530s
-------------------------------
Private project (20+ 3rd library needs archive to libapps.a)
-------------------------------
| Patched | Current
-------------------------------
|$ time make | $ time make
|real 0m21.181s | real 0m39.721s
|user 0m14.638s | user 0m24.837s
|sys 0m6.919s | sys 0m14.394s
-------------------------------
Signed-off-by: chao an <anchao@xiaomi.com>
so the user could generate the separate library through BIN.
Here is the similar code snippet copied from nuttx/tools/Unix.mk:
context: include/nuttx/config.h include/nuttx/version.h .dirlinks $(CONTEXTDIRS_DEPS) | staging
staging:
$(Q) mkdir -p $@
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
This is the corresponding change to the one on main NuttX repo. In this
case this involves splitting the build of libapps.a into: a) building
all applications (which is safely parallelizable), b) adding each
application's object files to the archive in turns (serial by nature).
This removes the need for the flock used to protect the parallel build.
