allow specific test for make check

Makefile.standalone

Index: Makefile.standalone
diff --git a/Makefile.standalone b/Makefile.standalone
index a91798587862156cd66aebf3f98f2b5ceaab3307..c820f8f4d9741e9532c12e8798f5458e38b5b0f9 100644
--- a/Makefile.standalone
+++ b/Makefile.standalone
@@ -33,6 +33,9 @@ PNACL_TOOLCHAIN_ROOT ?= $(shell readlink -e $(TOOLCHAIN_ROOT)/pnacl_newlib_raw)
 # The location of PNaCl tools (e.g., binutils objdump, pnacl-clang++, etc.).
 PNACL_BIN_PATH ?= $(shell readlink -e $(PNACL_TOOLCHAIN_ROOT)/bin)
 
+# Allow tests_lit to be overidden
+TESTS_LIT ?= tests_lit

[Jim Stichnoth, 2016/01/15 19:20:58]

Currently lit is used two situations:

1. "make check-lit" where you may want to run just one test to make it easier to
sift through the error spewage.

2. "make check-xtest" where you may want to run just one test because it takes
several minutes to run them all.

So I think two variables may be in order here.

CHECK_LIT_TESTS ?= tests_lit
CHECK_XTEST_TESTS ?= crosstest/Output

and then make a similar modification to the check-xtest lit command.

It would also be good to document the ?= assignment here with an example of a
single-test override, because I know I for one will continually revisit this
Makefile to remember how it's done.

+
 # Hack to auto-detect autoconf versus cmake build of LLVM.  If the LLVM tools
 # were dynamically linked with something like libLLVM-3.7svn.so, it is an
 # autoconf build, otherwise it is a cmake build.  AUTOCONF is set to 0 for
@@ -415,7 +418,7 @@ runtime.is.built: $(RT_SRC) pydir/build-runtime.py
 
 check-lit: $(OBJDIR)/pnacl-sz make_symlink
 	PNACL_BIN_PATH=$(PNACL_BIN_PATH) \
-	$(LLVM_SRC_PATH)/utils/lit/lit.py -sv tests_lit \
+	$(LLVM_SRC_PATH)/utils/lit/lit.py -sv $(TESTS_LIT) \
             $(FORCEASM_LIT_TEST_EXCLUDES) $(FORCEASM_LIT_PARAM)
 
 ifdef MINIMAL