[libcxx] r315876 - Really do make sure that last_write_time.pass.cpp still works with old clang

[Roman Lebedev via cfe-commits]

Author: lebedevri
Date: Sun Oct 15 13:46:12 2017
New Revision: 315876

URL: http://llvm.org/viewvc/llvm-project?rev=315876&view=rev
Log:
Really do make sure that last_write_time.pass.cpp still works with old clang

I *did* try to check that such kind of an issue was not introduced
by the rL315874, but clearly i failed to finish verification.

Modified:
    libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp

Modified: libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp?rev=315876&r1=315875&r2=315876&view=diff
==============================================================================
--- libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp (original)
+++ libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp Sun Oct 15 13:46:12 2017
@@ -89,9 +89,11 @@ bool TestSupportsNegativeTimes() {
 }
 
 // In some configurations, the comparison is tautological and the test is valid.
-// We disable the warning so that we can actually test it regardless.
+// We disable the warning so that we can actually test it regardless. Also, that
+// diagnostic is pretty new, so also don't fail if old clang does not support it
 #if defined(__clang__)
 #pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunknown-warning-option"
 #pragma clang diagnostic ignored "-Wtautological-constant-compare"
 #endif
 
@@ -123,9 +125,11 @@ static const bool SupportsMaxTime = Test
 } // end namespace
 
 // In some configurations, the comparison is tautological and the test is valid.
-// We disable the warning so that we can actually test it regardless.
+// We disable the warning so that we can actually test it regardless. Also, that
+// diagnostic is pretty new, so also don't fail if old clang does not support it
 #if defined(__clang__)
 #pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunknown-warning-option"
 #pragma clang diagnostic ignored "-Wtautological-constant-compare"
 #endif