[flang] Address comment: make CHECK test more explicit

Original-commit: flang-compiler/f18@a346462676b676d0abe2f98db2a80c8a4af3bd42
Reviewed-on: https://github.com/flang-compiler/f18/pull/600

diff --git a/flang/lib/semantics/resolve-names.cc b/flang/lib/semantics/resolve-names.cc
index dc8d1e8..2575f6c 100644 (file)
--- a/flang/lib/semantics/resolve-names.cc
+++ b/flang/lib/semantics/resolve-names.cc
@@ -4441,7 +4441,7 @@ ConstructVisitor::Selector ConstructVisitor::ResolveSelector(
 }
 
 ConstructVisitor::Association &ConstructVisitor::GetCurrentAssociation() {
-  CHECK(associationStack_.size());
+  CHECK(!associationStack_.empty());
   return associationStack_.back();
 }
 
@@ -4450,7 +4450,7 @@ void ConstructVisitor::PushAssociation() {
 }
 
 void ConstructVisitor::PopAssociation() {
-  CHECK(associationStack_.size());
+  CHECK(!associationStack_.empty());
   associationStack_.pop_back();
 }