[ASan] Fix leak tests on 64-bit targets other than x86-64 (take two)

[foad]

Summary

First, remove lit configuration that sets ASAN_OPTIONS to detect_leaks=1
because this is already the default when leak detection is supported.
This removes a bit of duplication between various lit.cfg files.

Second, add a new feature 'leak-detection' if we're targetting x86_64
(not i386) on Linux.

Third, change a couple of tests that need leak detection to require the
new 'leak-detection' feature.

[samsonov]

LGTM

[foad]

For the record, "take one" was D6189.

[earthdok]

lgtm

test/asan/TestCases/Linux/coverage-and-lsan.cc

 // Make sure coverage is dumped even if there are reported leaks.
 //
 // RUN: %clangxx_asan -fsanitize-coverage=1 %s -o %t
 //
 // RUN: rm -rf %T/coverage-and-lsan
 //
 // RUN: mkdir -p %T/coverage-and-lsan/normal
 // RUN: ASAN_OPTIONS=coverage=1:coverage_dir=%T/coverage-and-lsan:verbosity=1 not %run %t 2>&1 | FileCheck %s
 // RUN: %sancov print %T/coverage-and-lsan/*.sancov 2>&1
 //
-// REQUIRES: asan-64-bits
+// REQUIRES: leak-detection
 
 int *g = new int;
 int main(int argc, char **argv) {
   g = 0;
   return 0;
 }
 
 // CHECK: LeakSanitizer: detected memory leaks
 // CHECK: CovDump:

test/asan/TestCases/Linux/leak.cc

 // Minimal test for LeakSanitizer+AddressSanitizer.
-// REQUIRES: asan-64-bits
+// REQUIRES: leak-detection
 //
 // RUN: %clangxx_asan  %s -o %t
 // RUN: ASAN_OPTIONS=detect_leaks=1 not %run %t  2>&1 | FileCheck %s
 // RUN: ASAN_OPTIONS=""             not %run %t  2>&1 | FileCheck %s
 // RUN: ASAN_OPTIONS=detect_leaks=0     %run %t
 #include <stdio.h>
 int *t;
 
 int main(int argc, char **argv) {
   t = new int[argc - 1];
   printf("t: %p\n", t);
   t = 0;
 }
 // CHECK: LeakSanitizer: detected memory leaks

test/asan/Unit/lit.site.cfg.in

 # Setup test source and exec root. For unit tests, we define
 # it as build directory with ASan unit tests.
 # FIXME: De-hardcode this path.
 config.test_exec_root = "@COMPILER_RT_BINARY_DIR@/lib/asan/tests"
 config.test_source_root = config.test_exec_root
 
 # Set LD_LIBRARY_PATH to pick dynamic runtime up properly.
 push_ld_library_path(config, config.compiler_rt_libdir)
-
-# Enable leak detection in ASan unit tests on x86_64-linux.
-if config.host_os == 'Linux' and config.host_arch == 'x86_64':
-  config.environment['ASAN_OPTIONS'] = 'detect_leaks=1'

test/asan/lit.cfg

 config.available_features.add("asan-" + config.bits + "-bits")
 
 # Allow tests to use REQUIRES=stable-runtime.  For use when you cannot use XFAIL
 # because the test hangs.
 if config.target_arch != 'arm':
   config.available_features.add('stable-runtime')
 
 # Turn on leak detection on 64-bit Linux.
-if config.host_os == 'Linux' and config.bits == '64':
-  config.environment['ASAN_OPTIONS'] = 'detect_leaks=1'
+if config.host_os == 'Linux' and config.target_arch == 'x86_64':
+  config.available_features.add('leak-detection')
 
 # Set LD_LIBRARY_PATH to pick dynamic runtime up properly.
 push_ld_library_path(config, config.compiler_rt_libdir)
 
 # GCC-ASan uses dynamic runtime by default.
 if config.compiler_id == 'GNU':
   gcc_dir = os.path.dirname(config.clang)
   libasan_dir = os.path.join(gcc_dir, "..", "lib" + config.bits)

test/lsan/lit.common.cfg

 lsan_lit_test_mode = get_required_attr(config, 'lsan_lit_test_mode')
 if lsan_lit_test_mode == "Standalone":
   config.name = "LeakSanitizer-Standalone"
   lsan_cflags = ["-fsanitize=leak"]
 elif lsan_lit_test_mode == "AddressSanitizer":
   config.name = "LeakSanitizer-AddressSanitizer"
   lsan_cflags = ["-fsanitize=address"]
   config.available_features.add('asan')
-  config.environment['ASAN_OPTIONS'] = 'detect_leaks=1'
 else:
   lit_config.fatal("Unknown LSan test mode: %r" % lsan_lit_test_mode)
 
 clang_cflags = ["-O0", "-m64"] + config.debug_info_flags
 clang_cxxflags = config.cxx_mode_flags + clang_cflags
 clang_lsan_cflags = clang_cflags + lsan_cflags
 clang_lsan_cxxflags = clang_cxxflags + lsan_cflags