[Lldb-commits] [lldb] d1326a3 - [lldb] Fix broken skipUnlessUndefinedBehaviorSanitizer decorator

[Jonas Devlieghere via lldb-commits]

Author: Jonas Devlieghere
Date: 2021-11-30T13:03:33-08:00
New Revision: d1326a3b10054dd89be46f51f857d009cf8ae14f

URL: https://github.com/llvm/llvm-project/commit/d1326a3b10054dd89be46f51f857d009cf8ae14f
DIFF: https://github.com/llvm/llvm-project/commit/d1326a3b10054dd89be46f51f857d009cf8ae14f.diff

LOG: [lldb] Fix broken skipUnlessUndefinedBehaviorSanitizer decorator

727bd89b605b broke the UBSan decorator. The decorator compiles a custom
source code snippet that exposes UB and verifies the presence of a UBSan
symbol in the generated binary. The aforementioned commit broke both by
compiling a snippet without UB and discarding the result.

Added: 
    

Modified: 
    lldb/packages/Python/lldbsuite/test/decorators.py

Removed: 
    


################################################################################
diff  --git a/lldb/packages/Python/lldbsuite/test/decorators.py b/lldb/packages/Python/lldbsuite/test/decorators.py
index 972a98a13079..b6ef3f08df22 100644
--- a/lldb/packages/Python/lldbsuite/test/decorators.py
+++ b/lldb/packages/Python/lldbsuite/test/decorators.py
@@ -87,13 +87,16 @@ def _match_decorator_property(expected, actual):
         return expected == actual
 
 
-def _compiler_supports(compiler, flag):
+def _compiler_supports(compiler,
+                       flag,
+                       source='int main() {}',
+                       output_file=tempfile.NamedTemporaryFile()):
     """Test whether the compiler supports the given flag."""
     if platform.system() == 'Darwin':
         compiler = "xcrun " + compiler
-    f = tempfile.NamedTemporaryFile()
     try:
-        cmd = "echo 'int main() {}' | %s %s -x c -o %s -" % (compiler, flag, f.name)
+        cmd = "echo '%s' | %s %s -x c -o %s -" % (source, compiler, flag,
+                                                  output_file.name)
         subprocess.check_call(cmd, shell=True)
     except subprocess.CalledProcessError:
         return False
@@ -755,16 +758,13 @@ def is_compiler_clang_with_ubsan(self):
         if is_running_under_asan():
             return "Undefined behavior sanitizer tests are disabled when runing under ASAN"
 
-        # Write out a temp file which exhibits UB.
-        inputf = tempfile.NamedTemporaryFile(suffix='.c', mode='w')
-        inputf.write('int main() { int x = 0; return x / x; }\n')
-        inputf.flush()
-
         # We need to write out the object into a named temp file for inspection.
         outputf = tempfile.NamedTemporaryFile()
 
         # Try to compile with ubsan turned on.
-        if not _compiler_supports(self.getCompiler(), '-fsanitize=undefined'):
+        if not _compiler_supports(self.getCompiler(), '-fsanitize=undefined',
+                                  'int main() { int x = 0; return x / x; }',
+                                  outputf):
             return "Compiler cannot compile with -fsanitize=undefined"
 
         # Check that we actually see ubsan instrumentation in the binary.