[OPENMP] Fix assert fail after target implicit map checks.

If the error is generated during analysis of implicitly or explicitly
mapped variables, it may cause compiler crash because of incorrect
analysis.

llvm-svn: 319774

clang/lib/Sema/SemaOpenMP.cpp

@@ -1996,7 +1996,8 @@ public:
     }
     if (isOpenMPTargetExecutionDirective(DKind) && !FD->isBitField()) {
       OMPClauseMappableExprCommon::MappableExprComponentList CurComponents;
-      CheckMapClauseExpressionBase(SemaRef, E, CurComponents, OMPC_map);
+      if (!CheckMapClauseExpressionBase(SemaRef, E, CurComponents, OMPC_map))
+        return;
       auto *VD = cast<ValueDecl>(
           CurComponents.back().getAssociatedDeclaration()->getCanonicalDecl());
       if (!Stack->checkMappableExprComponentListsForDecl(
@@ -11467,7 +11468,7 @@ static Expr *CheckMapClauseExpressionBase(
 
     if (auto *CurE = dyn_cast<DeclRefExpr>(E)) {
       if (!isa<VarDecl>(CurE->getDecl()))
-        break;
+        return nullptr;
 
       RelevantExpr = CurE;
 
@@ -11477,12 +11478,8 @@ static Expr *CheckMapClauseExpressionBase(
       AllowWholeSizeArraySection = false;
 
       // Record the component.
-      CurComponents.push_back(OMPClauseMappableExprCommon::MappableComponent(
-          CurE, CurE->getDecl()));
-      continue;
-    }
-
-    if (auto *CurE = dyn_cast<MemberExpr>(E)) {
+      CurComponents.emplace_back(CurE, CurE->getDecl());
+    } else if (auto *CurE = dyn_cast<MemberExpr>(E)) {
       auto *BaseE = CurE->getBase()->IgnoreParenImpCasts();
 
       if (isa<CXXThisExpr>(BaseE))
@@ -11494,7 +11491,7 @@ static Expr *CheckMapClauseExpressionBase(
       if (!isa<FieldDecl>(CurE->getMemberDecl())) {
         SemaRef.Diag(ELoc, diag::err_omp_expected_access_to_data_field)
             << CurE->getSourceRange();
-        break;
+        return nullptr;
       }
 
       auto *FD = cast<FieldDecl>(CurE->getMemberDecl());
@@ -11505,7 +11502,7 @@ static Expr *CheckMapClauseExpressionBase(
       if (FD->isBitField()) {
         SemaRef.Diag(ELoc, diag::err_omp_bit_fields_forbidden_in_clause)
             << CurE->getSourceRange() << getOpenMPClauseName(CKind);
-        break;
+        return nullptr;
       }
 
       // OpenMP 4.5 [2.15.5.1, map Clause, Restrictions, C++, p.1]
@@ -11521,7 +11518,7 @@ static Expr *CheckMapClauseExpressionBase(
         if (RT->isUnionType()) {
           SemaRef.Diag(ELoc, diag::err_omp_union_type_not_allowed)
               << CurE->getSourceRange();
-          break;
+          return nullptr;
         }
 
       // If we got a member expression, we should not expect any array section
@@ -11535,18 +11532,14 @@ static Expr *CheckMapClauseExpressionBase(
       AllowWholeSizeArraySection = false;
 
       // Record the component.
-      CurComponents.push_back(
-          OMPClauseMappableExprCommon::MappableComponent(CurE, FD));
-      continue;
-    }
-
-    if (auto *CurE = dyn_cast<ArraySubscriptExpr>(E)) {
+      CurComponents.emplace_back(CurE, FD);
+    } else if (auto *CurE = dyn_cast<ArraySubscriptExpr>(E)) {
       E = CurE->getBase()->IgnoreParenImpCasts();
 
       if (!E->getType()->isAnyPointerType() && !E->getType()->isArrayType()) {
         SemaRef.Diag(ELoc, diag::err_omp_expected_base_var_name)
             << 0 << CurE->getSourceRange();
-        break;
+        return nullptr;
       }
 
       // If we got an array subscript that express the whole dimension we
@@ -11557,15 +11550,11 @@ static Expr *CheckMapClauseExpressionBase(
         AllowWholeSizeArraySection = false;
 
       // Record the component - we don't have any declaration associated.
-      CurComponents.push_back(
-          OMPClauseMappableExprCommon::MappableComponent(CurE, nullptr));
-      continue;
-    }
-
-    if (auto *CurE = dyn_cast<OMPArraySectionExpr>(E)) {
+      CurComponents.emplace_back(CurE, nullptr);
+    } else if (auto *CurE = dyn_cast<OMPArraySectionExpr>(E)) {
       E = CurE->getBase()->IgnoreParenImpCasts();
 
-      auto CurType =
+      QualType CurType =
           OMPArraySectionExpr::getBaseOriginalType(E).getCanonicalType();
 
       // OpenMP 4.5 [2.15.5.1, map Clause, Restrictions, C++, p.1]
@@ -11579,7 +11568,7 @@ static Expr *CheckMapClauseExpressionBase(
       if (!IsPointer && !CurType->isArrayType()) {
         SemaRef.Diag(ELoc, diag::err_omp_expected_base_var_name)
             << 0 << CurE->getSourceRange();
-        break;
+        return nullptr;
       }
 
       bool NotWhole =
@@ -11602,20 +11591,18 @@ static Expr *CheckMapClauseExpressionBase(
         SemaRef.Diag(
             ELoc, diag::err_array_section_does_not_specify_contiguous_storage)
             << CurE->getSourceRange();
-        break;
+        return nullptr;
       }
 
       // Record the component - we don't have any declaration associated.
-      CurComponents.push_back(
-          OMPClauseMappableExprCommon::MappableComponent(CurE, nullptr));
-      continue;
+      CurComponents.emplace_back(CurE, nullptr);
+    } else {
+      // If nothing else worked, this is not a valid map clause expression.
+      SemaRef.Diag(ELoc,
+                   diag::err_omp_expected_named_var_member_or_array_expression)
+          << ERange;
+      return nullptr;
     }
-
-    // If nothing else worked, this is not a valid map clause expression.
-    SemaRef.Diag(ELoc,
-                 diag::err_omp_expected_named_var_member_or_array_expression)
-        << ERange;
-    break;
   }
 
   return RelevantExpr;

clang/test/OpenMP/target_map_messages.cpp

@@ -269,6 +269,10 @@ void SAclient(int arg) {
   {}
   #pragma omp target map(u.B)  // expected-error {{mapped storage cannot be derived from a union}}
   {}
+  #pragma omp target
+  {
+    u.B = 0; // expected-error {{mapped storage cannot be derived from a union}}
+  }
 
   #pragma omp target data map(to: r.C) //expected-note {{used here}}
   {