diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 7f68fd877e4e2..e6d7a19051965 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -891,6 +891,8 @@ OpenMP Support
 - Added support 'no_openmp_constructs' assumption clause.
 - Added support for 'self_maps' in map and requirement clause.
 - Added support for 'omp stripe' directive.
+- Fixed a crashing bug with ``omp tile sizes`` if the argument to ``sizes`` was
+  an invalid expression. (#GH139073)
 
 Improvements
 ^^^^^^^^^^^^
diff --git a/clang/lib/Sema/SemaOpenMP.cpp b/clang/lib/Sema/SemaOpenMP.cpp
index 835dba22a858d..2534822b72f80 100644
--- a/clang/lib/Sema/SemaOpenMP.cpp
+++ b/clang/lib/Sema/SemaOpenMP.cpp
@@ -14328,6 +14328,10 @@ StmtResult SemaOpenMP::ActOnOpenMPTileDirective(ArrayRef<OMPClause *> Clauses,
   auto MakeDimTileSize = [&SemaRef = this->SemaRef, &CopyTransformer, &Context,
                           SizesClause, CurScope](int I) -> Expr * {
     Expr *DimTileSizeExpr = SizesClause->getSizesRefs()[I];
+
+    if (DimTileSizeExpr->containsErrors())
+      return nullptr;
+
     if (isa<ConstantExpr>(DimTileSizeExpr))
       return AssertSuccess(CopyTransformer.TransformExpr(DimTileSizeExpr));
 
@@ -14397,10 +14401,13 @@ StmtResult SemaOpenMP::ActOnOpenMPTileDirective(ArrayRef<OMPClause *> Clauses,
 
     // For cond-expression:
     //   .tile.iv < min(.floor.iv + DimTileSize, NumIterations)
+    Expr *DimTileSize = MakeDimTileSize(I);
+    if (!DimTileSize)
+      return StmtError();
     ExprResult EndOfTile = SemaRef.BuildBinOp(
         CurScope, LoopHelper.Cond->getExprLoc(), BO_Add,
         makeFloorIVRef(SemaRef, FloorIndVars, I, IVTy, OrigCntVar),
-        MakeDimTileSize(I));
+        DimTileSize);
     if (!EndOfTile.isUsable())
       return StmtError();
     ExprResult IsPartialTile =
@@ -14482,10 +14489,13 @@ StmtResult SemaOpenMP::ActOnOpenMPTileDirective(ArrayRef<OMPClause *> Clauses,
       return StmtError();
 
     // For incr-statement: .floor.iv += DimTileSize
+    Expr *DimTileSize = MakeDimTileSize(I);
+    if (!DimTileSize)
+      return StmtError();
     ExprResult IncrStmt = SemaRef.BuildBinOp(
         CurScope, LoopHelper.Inc->getExprLoc(), BO_AddAssign,
         makeFloorIVRef(SemaRef, FloorIndVars, I, IVTy, OrigCntVar),
-        MakeDimTileSize(I));
+        DimTileSize);
     if (!IncrStmt.isUsable())
       return StmtError();
 
diff --git a/clang/test/OpenMP/tile_messages.cpp b/clang/test/OpenMP/tile_messages.cpp
index 5268dfe97e0c8..e1f5155c924e5 100644
--- a/clang/test/OpenMP/tile_messages.cpp
+++ b/clang/test/OpenMP/tile_messages.cpp
@@ -161,3 +161,12 @@ void template_inst() {
   // expected-note@+1 {{in instantiation of function template specialization 'templated_func_type_dependent<int>' requested here}}
   templated_func_type_dependent<int>();
 }
+
+namespace GH139073 {
+void f(void) {
+  // Clang would previously crash on this because of the invalid DeclRefExpr.
+#pragma omp tile sizes(a) // expected-error {{use of undeclared identifier 'a'}}
+  for (int i = 0; i < 10; i++)
+    ;
+}
+} // namespace GH139073