[LLDB] Run MSVC STL atomic tests with PDB

[Nerixyz]

Because PDB doesn't know about templates, we need to get to T of std::atomic<T> differently. The type includes the value_type typedef, which is always equal to T. The native PDB plugin includes this since #169248.

Then we can run the std::atomic test with (native) PDB.

[llvmbot]

@llvm/pr-subscribers-lldb

Author: nerix (Nerixyz)

Changes

Because PDB doesn't know about templates, we need to get to T of std::atomic<T> differently. The type includes the value_type typedef, which is always equal to T. The native PDB plugin includes this since #169248.

Then we can run the std::atomic test with (native) PDB.

---

Full diff: https://github.com/llvm/llvm-project/pull/172349.diff

2 Files Affected:

• (modified) lldb/source/Plugins/Language/CPlusPlus/MsvcStlAtomic.cpp (+11-2)
• (modified) lldb/test/API/functionalities/data-formatter/data-formatter-stl/generic/atomic/TestDataFormatterStdAtomic.py (+2)

diff --git a/lldb/source/Plugins/Language/CPlusPlus/MsvcStlAtomic.cpp b/lldb/source/Plugins/Language/CPlusPlus/MsvcStlAtomic.cpp
index 020ba10166231..0e5464448c686 100644
--- a/lldb/source/Plugins/Language/CPlusPlus/MsvcStlAtomic.cpp
+++ b/lldb/source/Plugins/Language/CPlusPlus/MsvcStlAtomic.cpp
@@ -64,10 +64,19 @@ lldb_private::formatters::MsvcStlAtomicSyntheticFrontEnd::Update() {
   if (!storage_sp)
     return lldb::ChildCacheState::eRefetch;
 
-  m_element_type = m_backend.GetCompilerType().GetTypeTemplateArgument(0);
-  if (!m_element_type)
+  CompilerType backend_type = m_backend.GetCompilerType();
+  if (!backend_type)
     return lldb::ChildCacheState::eRefetch;
 
+  m_element_type = backend_type.GetTypeTemplateArgument(0);
+  if (!m_element_type) {
+    // PDB doesn't have info about templates, so use value_type which equals T.
+    m_element_type = backend_type.GetDirectNestedTypeWithName("value_type");
+
+    if (!m_element_type)
+      return lldb::ChildCacheState::eRefetch;
+  }
+
   m_storage = storage_sp.get();
   return lldb::ChildCacheState::eRefetch;
 }
diff --git a/lldb/test/API/functionalities/data-formatter/data-formatter-stl/generic/atomic/TestDataFormatterStdAtomic.py b/lldb/test/API/functionalities/data-formatter/data-formatter-stl/generic/atomic/TestDataFormatterStdAtomic.py
index bdf12ca3b86db..67c2c359c9afb 100644
--- a/lldb/test/API/functionalities/data-formatter/data-formatter-stl/generic/atomic/TestDataFormatterStdAtomic.py
+++ b/lldb/test/API/functionalities/data-formatter/data-formatter-stl/generic/atomic/TestDataFormatterStdAtomic.py
@@ -10,6 +10,8 @@
 
 
 class StdAtomicTestCase(TestBase):
+    TEST_WITH_PDB_DEBUG_INFO = True
+
     def get_variable(self, name):
         var = self.frame().FindVariable(name)
         var.SetPreferDynamicValue(lldb.eDynamicCanRunTarget)