[llvm] Document "%T" as deprecated in TestingGuide.rst

Differential Revision: https://reviews.llvm.org/D48189

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335080 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/docs/TestingGuide.rst b/docs/TestingGuide.rst
index a27da0d..3cc8cf4 100644 (file)
--- a/docs/TestingGuide.rst
+++ b/docs/TestingGuide.rst
@@ -460,7 +460,10 @@ RUN lines:
    Example: ``/home/user/llvm.build/test/MC/ELF/Output/foo_test.s.tmp``
 
 ``%T``
-   Directory of ``%t``.
+   Directory of ``%t``. Deprecated. Shouldn't be used, because it can be easily
+   misused and cause race conditions between tests.
+
+   Use ``rm -rf %t && mkdir %t`` instead if a temporary directory is necessary.
 
    Example: ``/home/user/llvm.build/test/MC/ELF/Output``