https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118477
Bug ID: 118477
Summary: Race condition in 'd' Make-lang.in
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: d
Assignee: ibuclaw at gdcproject dot org
Reporter: clyon at gcc dot gnu.org
Target Milestone: ---
In our CI with highly parallel builds, we have noticed random failures in the
'd' front-end, with errors like:
mv: cannot stat 'd/.deps/package.TPo': No such file or directory
My analysis is that the problem is caused by identical filenames in different
subdirs:
common/file.d
mangle/package.d
visitor/package.d
root/file.d
Make-lang.in contains for instance:
d/visitor-%.o: d/dmd/visitor/%.d
$(DCOMPILE) $(D_INCLUDES) $<
$(DPOSTCOMPILE)
which means that in DCOMPILE, we have $@ == d/visitor-package.o (which is OK)
but in DCOMPILE and DPOSTCOMPILE, we have $(@D) == 'd' and $(*F) == 'package'
so, while mangle/package.d and visitor/package.d have different targets
(d/mangle-package.o and d/visitor-mangle.o), their deps (.TPo) file is
identical: d/.deps/package.TPo
since DCOMPILE and DPOSTCOMPILE are present in other Make-lang.in instances,
I'm not sure it's OK to modify them.
OTOH, a simple fix is to make sure there are no files with the same names in
such subdirs, but how would we enforce that in the long term?
