[-gmodules] Let LLDB log a warning if the Clang module hash mismatches.

This feature is mostly there to aid debugging of Clang module issues,
since the only useful actual the end-user can to is to recompile their
program.

Differential Revision: https://reviews.llvm.org/D70272

1 files changed, 49 insertions, 0 deletions

diff --git a/lldb/packages/Python/lldbsuite/test/lang/objc/modules-hash-mismatch/TestClangModulesHashMismatch.py b/lldb/packages/Python/lldbsuite/test/lang/objc/modules-hash-mismatch/TestClangModulesHashMismatch.py
new file mode 100644
index 00000000000..298e26ee400
--- /dev/null
+++ b/lldb/packages/Python/lldbsuite/test/lang/objc/modules-hash-mismatch/TestClangModulesHashMismatch.py
@@ -0,0 +1,49 @@
+from __future__ import print_function
+
+import unittest2
+import os
+import shutil
+
+import lldb
+from lldbsuite.test.decorators import *
+from lldbsuite.test.lldbtest import *
+from lldbsuite.test import lldbutil
+
+
+class TestClangModuleHashMismatch(TestBase):
+    mydir = TestBase.compute_mydir(__file__)
+
+    def setUp(self):
+        TestBase.setUp(self)
+
+    @skipUnlessDarwin
+    @skipIf(debug_info=no_match(["gmodules"]))
+    def test_expr(self):
+        with open(self.getBuildArtifact("module.modulemap"), "w") as f:
+            f.write("""
+                    module Foo { header "f.h" }
+                    """)
+        with open(self.getBuildArtifact("f.h"), "w") as f:
+            f.write("""
+                    typedef int my_int;
+                    void f() {}
+                    """)
+
+        mod_cache = self.getBuildArtifact("private-module-cache")
+        if os.path.isdir(mod_cache):
+          shutil.rmtree(mod_cache)
+        self.build()
+        self.assertTrue(os.path.isdir(mod_cache), "module cache exists")
+
+        logfile = self.getBuildArtifact("host.log")
+        self.runCmd("log enable -v -f %s lldb host" % logfile)
+        target, _, _, _ = lldbutil.run_to_source_breakpoint(
+            self, "break here", lldb.SBFileSpec("main.m"))
+        target.GetModuleAtIndex(0).FindTypes('my_int') 
+
+        found = False
+        with open(logfile, 'r') as f:
+            for line in f:
+                if "hash mismatch" in line and "Foo" in line:
+                    found = True
+        self.assertTrue(found)