The workflow pre-created build\c with a protected DACL so build
products would inherit it, but the diagnostic note from the failing CI
shard named the real actor: MSYS2's Cygwin layer writes POSIX-emulating
DACLs — including a CREATOR OWNER (S-1-3-0) mutation grant — onto
directories its tools touch, overwriting the pre-created shape during
the build. The activation transaction's source-directory policy
correctly refuses that grant, so the install-flow tests failed on CI
while the VM (whose harness stamps AFTER building) stayed green.
The stamp now runs inside run-tests-parallel.sh on Windows, after any
builder has had its say and immediately before the suites — one code
path for CI and the VM. Two idempotent steps, as before: protect the
directory, then /reset the children onto the clean inherited set.
Verified: full VM parallel run green (6669 passed, 0 failed) through
the new path.
Signed-off-by: Martin Vogel <martin.vogel.tech@gmail.com>
Martin Vogel
04141465ee