diff --git a/src/cmd/compile/internal/escape/utils.go b/src/cmd/compile/internal/escape/utils.go
index 2c6e9bcbeb..b481d8e4b6 100644
--- a/src/cmd/compile/internal/escape/utils.go
+++ b/src/cmd/compile/internal/escape/utils.go
@@ -7,6 +7,7 @@ package escape
 import (
 	"cmd/compile/internal/ir"
 	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
 )
 
 func isSliceSelfAssign(dst, src ir.Node) bool {
@@ -185,10 +186,16 @@ func HeapAllocReason(n ir.Node) string {
 	if n.Type().Size() > ir.MaxStackVarSize {
 		return "too large for stack"
 	}
+	if n.Type().Alignment() > int64(types.PtrSize) {
+		return "too aligned for stack"
+	}
 
 	if (n.Op() == ir.ONEW || n.Op() == ir.OPTRLIT) && n.Type().Elem().Size() > ir.MaxImplicitStackVarSize {
 		return "too large for stack"
 	}
+	if (n.Op() == ir.ONEW || n.Op() == ir.OPTRLIT) && n.Type().Elem().Alignment() > int64(types.PtrSize) {
+		return "too aligned for stack"
+	}
 
 	if n.Op() == ir.OCLOSURE && typecheck.ClosureType(n.(*ir.ClosureExpr)).Size() > ir.MaxImplicitStackVarSize {
 		return "too large for stack"