[flang-commits] [flang] [flang][OpenMP] Fix crash in unparse-with-symbols for CRITICAL (PR #151962)

[Krzysztof Parzyszek via flang-commits]

https://github.com/kparzysz created https://github.com/llvm/llvm-project/pull/151962

None

>From 73171dd21e3e14bcf0f25e4b5e6e4ab3679ad7d5 Mon Sep 17 00:00:00 2001
From: Krzysztof Parzyszek <Krzysztof.Parzyszek at amd.com>
Date: Mon, 4 Aug 2025 07:59:47 -0500
Subject: [PATCH] [flang][OpenMP] Fix crash in unparse-with-symbols for
 CRITICAL

---
 flang/lib/Semantics/unparse-with-symbols.cpp  | 33 +++++++++++++++++++
 .../OpenMP/critical-unparse-with-symbols.f90  | 21 ++++++++++++
 2 files changed, 54 insertions(+)
 create mode 100644 flang/test/Parser/OpenMP/critical-unparse-with-symbols.f90

diff --git a/flang/lib/Semantics/unparse-with-symbols.cpp b/flang/lib/Semantics/unparse-with-symbols.cpp
index f1e2e4ea7f119..4548fbeba5df6 100644
--- a/flang/lib/Semantics/unparse-with-symbols.cpp
+++ b/flang/lib/Semantics/unparse-with-symbols.cpp
@@ -70,6 +70,39 @@ class SymbolDumpVisitor {
     currStmt_ = std::nullopt;
   }
 
+  bool Pre(const parser::OmpCriticalDirective &x) {
+    currStmt_ = x.source;
+    return true;
+  }
+  void Post(const parser::OmpCriticalDirective &) {
+    currStmt_ = std::nullopt;
+  }
+
+  bool Pre(const parser::OmpEndCriticalDirective &x) {
+    currStmt_ = x.source;
+    return true;
+  }
+  void Post(const parser::OmpEndCriticalDirective &) {
+    currStmt_ = std::nullopt;
+  }
+
+  // Directive arguments can be objects with symbols.
+  bool Pre(const parser::OmpBeginDirective &x) {
+    currStmt_ = x.source;
+    return true;
+  }
+  void Post(const parser::OmpBeginDirective &) {
+    currStmt_ = std::nullopt;
+  }
+
+  bool Pre(const parser::OmpEndDirective &x) {
+    currStmt_ = x.source;
+    return true;
+  }
+  void Post(const parser::OmpEndDirective &) {
+    currStmt_ = std::nullopt;
+  }
+
 private:
   std::optional<SourceName> currStmt_; // current statement we are processing
   std::multimap<const char *, const Symbol *> symbols_; // location to symbol
diff --git a/flang/test/Parser/OpenMP/critical-unparse-with-symbols.f90 b/flang/test/Parser/OpenMP/critical-unparse-with-symbols.f90
new file mode 100644
index 0000000000000..4d0d93ac48740
--- /dev/null
+++ b/flang/test/Parser/OpenMP/critical-unparse-with-symbols.f90
@@ -0,0 +1,21 @@
+!RUN: %flang_fc1 -fdebug-unparse-with-symbols -fopenmp -fopenmp-version=50 %s | FileCheck --ignore-case --check-prefix="UNPARSE" %s
+
+subroutine f
+  implicit none
+  integer :: x
+  !$omp critical(c)
+  x = 0
+  !$omp end critical(c)
+end
+
+!UNPARSE: !DEF: /f (Subroutine) Subprogram
+!UNPARSE: subroutine f
+!UNPARSE:  implicit none
+!UNPARSE:  !DEF: /f/x ObjectEntity INTEGER(4)
+!UNPARSE:  integer x
+!UNPARSE: !$omp critical (c)
+!UNPARSE:  !REF: /f/x
+!UNPARSE:  x = 0
+!UNPARSE: !$omp end critical (c)
+!UNPARSE: end subroutine
+