778508 - mfbt symlinks installed by both base and js

Status: NEW

(Firefox Build System :: General, defect)

Description

[Gregory Szorc [:gps]]

It appears that both the base and js tiers install mfbt header files into dist/include/mozilla/.

STR:

1) |make tier_base|
2) Stash objdir somewhere (I do a |git init; git add *|)
3) |make tier_nspr|
4) |make tier_js|
5) Diff objdir/dist/include/mozilla

You'll notice the following symlinks change:

dist/include/mozilla/Assertions.h
dist/include/mozilla/Attributes.h
dist/include/mozilla/BloomFilter.h
dist/include/mozilla/CheckedInt.h
dist/include/mozilla/FloatingPoint.h
dist/include/mozilla/GuardObjects.h
dist/include/mozilla/HashFunctions.h
dist/include/mozilla/Likely.h
dist/include/mozilla/LinkedList.h
dist/include/mozilla/MSStdInt.h
dist/include/mozilla/RangedPtr.h
dist/include/mozilla/RefPtr.h
dist/include/mozilla/Scoped.h
dist/include/mozilla/StandardInteger.h
dist/include/mozilla/ThreadLocal.h
dist/include/mozilla/TypeTraits.h
dist/include/mozilla/Types.h
dist/include/mozilla/Util.h

Before, (with the base tier) the symlinks look like:

 /Users/gps/src/mozilla-central-git/mfbt/Assertions.h

Afterward, (with the js tier) they look like:

 /Users/gps/src/mozilla-central-git/js/src/../../mfbt/Assertions.h

These do resolve to the same file. But, the symlink is being replaced.

As far as invalidating the make target and causing extra work for make, I don't think it is an issue. stat() by default will report on the target of a symlink. If make used lstat() to look up mtimes, we might be in trouble. I audited GNU make's source code and only found one reference to lstat(). And, it is only called when -L/--check-symlink-times is present on the command line.

So, I think this bug is just a nuisance, nothing more. I can understand if someone closes it WONTFIX.