[asan][test][win] Set __COMPAT_LAYER=RunAsInvoker when running tests

[alvinhochun]

Summary

The TestCases/asan_update_allocation.cpp test on i686 MinGW target
happens to trigger a heuristic on Windows which makes it want to run as
elevated, probably because its name contains "update". This makes the
test fail when not running with elevated privileges.

Setting this environment variable tells Windows to ignore the
requirement to run as elevated, allowing the test to pass. This is the
same approach taken in https://reviews.llvm.org/D137772.

[mstorsjo]

LGTM, thanks!

I’ve got a similar change in queue for builtins tests too, for trampoline_setup_test.c (triggered on aarch64), I guess I should post that patch too.

[alvinhochun]

So we have three places that need this now, I wonder if it makes more sense to make this a builtin feature of lit?

[mstorsjo]

In D148988#4291724, @alvinhochun wrote:

So we have three places that need this now, I wonder if it makes more sense to make this a builtin feature of lit?

I guess that could make sense at this point! I'm fairly sure that no tests under lit would want the setup/installer heuristic to fire.

[alvinhochun]

Superseded by D149064.

compiler-rt/test/asan/lit.cfg.py

 if config.host_os not in ['Linux', 'Darwin', 'FreeBSD', 'SunOS', 'Windows', 'NetBSD']:
   config.unsupported = True
 
 if not config.parallelism_group:
   config.parallelism_group = 'shadow-memory'
 
 if config.host_os == 'NetBSD':
   config.substitutions.insert(0, ('%run', config.netbsd_noaslr_prefix))
+
+# Avoid Windows heuristics which try to detect potential installer programs
+# (which may need to run with elevated privileges) and ask if the user wants
+# to run them in that way. This heuristic may match for executables containing
+# the word "update", e.g. `TestCases/asan_update_allocation.cpp`. Set an
+# environment variable indicating that we want to execute them with the current
+# user.
+if config.host_os == 'Windows':
+    config.environment['__COMPAT_LAYER'] = 'RunAsInvoker'