[flang][OpenMP] Fix goto within SECTION

flang/lib/Semantics/resolve-directives.cpp

@@ -384,6 +384,9 @@ class OmpAttributeVisitor : DirectiveAttributeVisitor<llvm::omp::Directive> {
   bool Pre(const parser::OpenMPSectionsConstruct &);
   void Post(const parser::OpenMPSectionsConstruct &) { PopContext(); }
 
+  bool Pre(const parser::OpenMPSectionConstruct &);
+  void Post(const parser::OpenMPSectionConstruct &) { PopContext(); }
+
   bool Pre(const parser::OpenMPCriticalConstruct &critical);
   void Post(const parser::OpenMPCriticalConstruct &) { PopContext(); }
 
@@ -2003,6 +2006,12 @@ bool OmpAttributeVisitor::Pre(const parser::OpenMPSectionsConstruct &x) {
   return true;
 }
 
+bool OmpAttributeVisitor::Pre(const parser::OpenMPSectionConstruct &x) {
+  PushContext(x.source, llvm::omp::Directive::OMPD_section);
+  GetContext().withinConstruct = true;
+  return true;
+}
+
 bool OmpAttributeVisitor::Pre(const parser::OpenMPCriticalConstruct &x) {
   const auto &beginCriticalDir{std::get<parser::OmpCriticalDirective>(x.t)};
   const auto &endCriticalDir{std::get<parser::OmpEndCriticalDirective>(x.t)};
@@ -3024,8 +3033,13 @@ void OmpAttributeVisitor::CheckLabelContext(const parser::CharBlock source,
     const parser::CharBlock target, std::optional<DirContext> sourceContext,
     std::optional<DirContext> targetContext) {
   auto dirContextsSame = [](DirContext &lhs, DirContext &rhs) -> bool {
-    // Sometimes nested constructs share a scope but are different contexts
-    return (lhs.scope == rhs.scope) && (lhs.directive == rhs.directive);
+    // Sometimes nested constructs share a scope but are different contexts.
+    // The directiveSource comparison is for OmpSection. Sections do not have
+    // their own scopes and two different sections both have the same directive.
+    // Their source however is different. This string comparison is unfortunate
+    // but should only happen for GOTOs inside of SECTION.
+    return (lhs.scope == rhs.scope) && (lhs.directive == rhs.directive) &&
+        (lhs.directiveSource == rhs.directiveSource);
   };
   unsigned version{context_.langOptions().OpenMPVersion};
   if (targetContext &&

flang/test/Semantics/OpenMP/parallel-sections01.f90

@@ -35,6 +35,8 @@ program OmpConstructSections01
    !$omp section
    print *, "This is a single statement structured block"
    !$omp section
+   !ERROR: invalid branch into an OpenMP structured block
+   !ERROR: invalid branch leaving an OpenMP structured block
    open (10, file="random-file-name.txt", err=30)
    !ERROR: invalid branch into an OpenMP structured block
    !ERROR: invalid branch leaving an OpenMP structured block

flang/test/Semantics/OpenMP/sections-goto.f90

@@ -0,0 +1,11 @@
+! RUN: %python %S/../test_errors.py %s %flang -fopenmp
+! Regression test for #143231
+
+!$omp sections
+! ERROR: invalid branch into an OpenMP structured block
+! ERROR: invalid branch leaving an OpenMP structured block
+goto 10
+!$omp section
+10 print *, "Invalid jump"
+!$omp end sections
+end

flang/test/Semantics/OpenMP/sections02.f90

@@ -19,6 +19,8 @@ program OmpConstructSections01
    !$omp section
    print *, "This is a single statement structured block"
    !$omp section
+   !ERROR: invalid branch into an OpenMP structured block
+   !ERROR: invalid branch leaving an OpenMP structured block
    open (10, file="random-file-name.txt", err=30)
    !ERROR: invalid branch into an OpenMP structured block
    !ERROR: invalid branch leaving an OpenMP structured block