[lldb] Use the just-built libc++ for testing the LLDB data formatters

Make sure we use the libc++ from the build dir. Currently, by passing
-stdlib=libc++, we might pick up the system libc++. This change ensures
that if LLVM_LIBS_DIR is set, we try to use the libc++ from there.

Differential revision: https://reviews.llvm.org/D129166

4 files changed, 16 insertions, 1 deletions

diff --git a/lldb/packages/Python/lldbsuite/test/builders/builder.py b/lldb/packages/Python/lldbsuite/test/builders/builder.py
index 9805706..cb82dd4 100644
--- a/lldb/packages/Python/lldbsuite/test/builders/builder.py
+++ b/lldb/packages/Python/lldbsuite/test/builders/builder.py
@@ -120,6 +120,11 @@ class Builder:
                 configuration.clang_module_cache_dir)]
         return []
 
+    def getLibCxxArgs(self):
+        if configuration.hermetic_libcxx:
+            return ["USE_HERMETIC_LIBCPP=1"]
+        return []
+
     def _getDebugInfoArgs(self, debug_info):
         if debug_info is None:
             return []
@@ -142,7 +147,7 @@ class Builder:
             self.getArchCFlags(architecture), self.getArchSpec(architecture),
             self.getCCSpec(compiler), self.getExtraMakeArgs(),
             self.getSDKRootSpec(), self.getModuleCacheSpec(),
-            self.getCmdLine(dictionary)]
+            self.getLibCxxArgs(), self.getCmdLine(dictionary)]
         command = list(itertools.chain(*command_parts))
 
         return command
diff --git a/lldb/packages/Python/lldbsuite/test/configuration.py b/lldb/packages/Python/lldbsuite/test/configuration.py
index 6b3da8f..c29a44e 100644
--- a/lldb/packages/Python/lldbsuite/test/configuration.py
+++ b/lldb/packages/Python/lldbsuite/test/configuration.py
@@ -124,6 +124,9 @@ all_tests = set()
 # LLDB library directory.
 lldb_libs_dir = None
 
+# Force us to use the just-built libcxx
+hermetic_libcxx = False
+
 # A plugin whose tests will be enabled, like intel-pt.
 enabled_plugins = []
 
diff --git a/lldb/packages/Python/lldbsuite/test/dotest.py b/lldb/packages/Python/lldbsuite/test/dotest.py
index a9ca741..ee59500 100644
--- a/lldb/packages/Python/lldbsuite/test/dotest.py
+++ b/lldb/packages/Python/lldbsuite/test/dotest.py
@@ -281,6 +281,11 @@ def parseOptionsAndInitTestdirs():
         logging.warning('No valid FileCheck executable; some tests may fail...')
         logging.warning('(Double-check the --llvm-tools-dir argument to dotest.py)')
 
+    configuration.hermetic_libcxx = args.hermetic_libcxx
+    if configuration.hermetic_libcxx and args.lldb_platform_name:
+        configuration.hermetic_libcxx = False
+        logging.warning('Hermetic libc++ is not supported for remote runs: ignoring --hermetic-libcxx')
+
     if args.channels:
         lldbtest_config.channels = args.channels
 
diff --git a/lldb/packages/Python/lldbsuite/test/dotest_args.py b/lldb/packages/Python/lldbsuite/test/dotest_args.py
index aac2fec..768b052 100644
--- a/lldb/packages/Python/lldbsuite/test/dotest_args.py
+++ b/lldb/packages/Python/lldbsuite/test/dotest_args.py
@@ -43,6 +43,8 @@ def create_parser():
     if sys.platform == 'darwin':
         group.add_argument('--apple-sdk', metavar='apple_sdk', dest='apple_sdk', default="", help=textwrap.dedent(
             '''Specify the name of the Apple SDK (macosx, macosx.internal, iphoneos, iphoneos.internal, or path to SDK) and use the appropriate tools from that SDK's toolchain.'''))
+    group.add_argument('--hermetic-libcxx', action='store_true', help=textwrap.dedent(
+        '''Force the just-built libcxx to be used for the libc++ formatter tests.'''))
     # FIXME? This won't work for different extra flags according to each arch.
     group.add_argument(
         '-E',