tree cca67c70b0e49e8ab9cfc920b79708f6154be234
parent 2ddc376cc3c5531db80899ce757861fac7a531b9
author Dan Willemsen <dwillemsen@google.com> 1557017719 -0700
committer Dan Willemsen <dwillemsen@google.com> 1578527731 -0800

Add option to require commands to create all outputs

If an output file wasn't created, then running the same build again
without changes would mark the edge as dirty and re-run the command.
This is an easy way to make incremental builds much longer than they
should be.

Commands that don't actually write outputs should be using `phony_output`

The default `-w missingoutfile=warn` will just print a warning when an
output isn't created. `-w missingoutfile=err` will fail the command when
an output isn't created.

Test: ninja_tests  (run by build-prebuilts.sh)
Change-Id: I1f4b1ee06f406b01b9263dcda7c6412eef4431ad