diff --git a/flang/include/flang/Parser/provenance.h b/flang/include/flang/Parser/provenance.h
--- a/flang/include/flang/Parser/provenance.h
+++ b/flang/include/flang/Parser/provenance.h
@@ -173,7 +173,6 @@
   std::string GetPath(Provenance) const; // __FILE__
   int GetLineNumber(Provenance) const; // __LINE__
   Provenance CompilerInsertionProvenance(char ch);
-  Provenance CompilerInsertionProvenance(const char *, std::size_t);
   ProvenanceRange IntersectionWithSourceFiles(ProvenanceRange) const;
   llvm::raw_ostream &Dump(llvm::raw_ostream &) const;
 
diff --git a/flang/include/flang/Semantics/symbol.h b/flang/include/flang/Semantics/symbol.h
--- a/flang/include/flang/Semantics/symbol.h
+++ b/flang/include/flang/Semantics/symbol.h
@@ -356,7 +356,7 @@
 };
 
 // Record the USE of a symbol: location is where (USE statement or renaming);
-// symbol is the USEd module.
+// symbol is in the USEd module.
 class UseDetails {
 public:
   UseDetails(const SourceName &location, const Symbol &symbol)
diff --git a/flang/lib/Semantics/assignment.cpp b/flang/lib/Semantics/assignment.cpp
--- a/flang/lib/Semantics/assignment.cpp
+++ b/flang/lib/Semantics/assignment.cpp
@@ -70,7 +70,7 @@
       const Scope &scope{context_.FindScope(lhsLoc)};
       if (auto whyNot{WhyNotModifiable(lhsLoc, lhs, scope, true)}) {
         if (auto *msg{Say(lhsLoc,
-                "Left-hand side of assignment is not modifiable"_err_en_US)}) { // C1158
+                "Left-hand side of assignment is not modifiable"_err_en_US)}) {
           msg->Attach(*whyNot);
         }
       }
diff --git a/flang/tools/f18/flang b/flang/tools/f18/flang
--- a/flang/tools/f18/flang
+++ b/flang/tools/f18/flang
@@ -12,4 +12,9 @@
 if [[ ! -d $module_dir ]]; then
   module_dir=$wd/tools/flang/include/flang
 fi
-$wd/bin/f18 -module-suffix .f18.mod -intrinsic-module-directory $module_dir "$@"
+opts="-module-suffix .f18.mod -intrinsic-module-directory $module_dir"
+if ! $wd/bin/f18 $opts "$@"
+then status=$?
+     echo flang: in $PWD, f18 failed with exit status $status: $wd/bin/f18 $opts "$@" >&2
+     exit $status
+fi