Problem building `make -j 4 all check` on Linux + GNU make

[jimklimov]

Originally discussed in #1853 (comment)

Reproduced across CentOS 7 (GNU make-3.82-24.el7.x86_64, automake-1.13.4-3.el7.noarch, autoconf-2.69-11.el7.noarch) - Debian 11 (GNU make 4.3-4.1, autoconf 2.69-14, automake 1.16.3-2) - Ubuntu 21.10 (GNU make 4.3-4ubuntu1, autoconf 2.69-14, automake 1.16.4-2) range.

NOT reproduced on OpenIndiana (Sun make, automake 1.16.5, autoconf 2.71) and OpenBSD 6.5 (BSD make, AUTOCONF_VERSION=2.69, AUTOMAKE_VERSION=1.13).

It seems that the two CLI goals are processed independently by GNU make (there are indeed no explicit lines like check: all to bind them in a Makefile.am) so the two trees of make child processes build same things, overwriting each other, moving away temporary files, etc. Per evidence, other Make implementations handle this more smartly to queue deeper "shared" recipes for these goals.

A quick shot at adding check: all in the top-level Makefile.am did not help; should try adding this to all of them. Or maybe try with check-local.

Notably, de-facto at the moment the make check alone builds everything from make all (the latter has nothing to do if called after a check made from scratch) and then some for test code, but generally this should not be relied upon - in projects I've seen, scopes did differ without a 100% overlap with all sometimes.

[jimklimov]

Docs updated to not suggest these two goals in one command for now.

[jimklimov]

Adding check: all and check-local: all dependencies into all Makefile.am files did not help.

[jimklimov]

For now leaving it be, did not bite anyone until recently (when parallel make all check got suggested by wiki). Per googling, seems to be a long-standing problem with GNU make, typically to make -j N clean all where people expect the CLI goals to be sequential and they are not, so freshly-built files are deleted sometimes.