[flang][Semantics] Fix updating flags of threadprivate symbols in presence of default clause

[NimishMishra]

Current semantic checks of default clause incorrectly update symbol flags related to threadprivate symbols. This patch adds an additional check to skip such updation should a symbol be already declared threadprivate.

Fixes #78282

[llvmbot]

@llvm/pr-subscribers-flang-fir-hlfir
@llvm/pr-subscribers-flang-openmp

@llvm/pr-subscribers-flang-semantics

Author: None (NimishMishra)

Changes

Current semantic checks of default clause incorrectly update symbol flags related to threadprivate symbols. This patch adds an additional check to skip such updation should a symbol be already declared threadprivate.

Fixes #78282

---

Full diff: https://github.com/llvm/llvm-project/pull/78283.diff

1 Files Affected:

• (modified) flang/lib/Semantics/resolve-directives.cpp (+5)

diff --git a/flang/lib/Semantics/resolve-directives.cpp b/flang/lib/Semantics/resolve-directives.cpp
index b30b81cf90c9517..c3e5578fe72f034 100644
--- a/flang/lib/Semantics/resolve-directives.cpp
+++ b/flang/lib/Semantics/resolve-directives.cpp
@@ -1958,6 +1958,11 @@ void OmpAttributeVisitor::Post(const parser::Name &name) {
         }
       }
     }
+
+    if (Symbol * found{currScope().FindSymbol(name.source)}) {
+      if (found->test(semantics::Symbol::Flag::OmpThreadprivate))
+        return;
+    }
     std::vector<Symbol *> defaultDSASymbols;
     for (int dirDepth{0}; dirDepth < (int)dirContext_.size(); ++dirDepth) {
       DirContext &dirContext = dirContext_[dirDepth];

[luporl]

It would be nice to add a test for this.

[NimishMishra]

It would be nice to add a test for this.

Thank you @luporl for the comment! I've added a test case.

[luporl]

The test case looks good, thanks!

Skipping threadprivate symbols from default clause processing makes sense to me.

[NimishMishra]

Ping for review!

[kiranchandramohan]

LGTM.