Report executePrintValue errors with DiagnosticsEngine.

Author: marsupial

lib/Interpreter/ValuePrinter.cpp

@@ -23,6 +23,7 @@
 #include "clang/AST/DeclCXX.h"
 #include "clang/AST/Expr.h"
 #include "clang/AST/Type.h"
+#include "clang/Sema/SemaDiagnostic.h"
 #include "clang/Frontend/CompilerInstance.h"
 
 #include "llvm/Support/Format.h"
@@ -144,22 +145,6 @@ struct AccessCtrlRAII_t {
 
 };
 
-#ifndef NDEBUG
-/// Is typenam parsable?
-bool canParseTypeName(cling::Interpreter& Interp, llvm::StringRef typenam) {
-
-  AccessCtrlRAII_t AccessCtrlRAII(Interp);
-
-  cling::Interpreter::CompilationResult Res
-    = Interp.declare("namespace { void* cling_printValue_Failure_Typename_check"
-                     " = (void*)" + typenam.str() + "nullptr; }");
-  if (Res != cling::Interpreter::kSuccess)
-    cling::errs() << "ERROR in cling::canParseTypeName(): "
-                     "this typename cannot be spelled.\n";
-  return Res == cling::Interpreter::kSuccess;
-}
-#endif
-
 static std::string printDeclType(const clang::QualType& QT,
                                  const clang::NamedDecl* D) {
   if (!QT.hasQualifiers())
@@ -609,14 +594,13 @@ static std::string callPrintValue(const Value& V, const void* Val) {
   if (printValueV.isValid() && printValueV.getPtr())
     return *(std::string *) printValueV.getPtr();
 
-  // That didn't work. We probably diagnosed the issue as part of evaluate().
-  cling::errs() <<"ERROR in cling's callPrintValue(): cannot pass value!\n";
-
-  // Check that the issue comes from an unparsable type name: lambdas, unnamed
-  // namespaces, types declared inside functions etc. Assert on everything
-  // else.
-  assert(!canParseTypeName(*Interp, getTypeString(V))
-         && "printValue failed on a valid type name.");
+  // Probably diagnosed the issue as part of evaluate(), but make sure to
+  // mark the Sema with an error if not.
+  clang::DiagnosticsEngine& Diag = Interp->getDiagnostics();
+  const unsigned ID = Diag.getCustomDiagID(
+                             clang::DiagnosticsEngine::Level::Error,
+                             "Could not execute cling::printValue with '%0'");
+  Diag.Report(Interp->getSourceLocation(), ID) << getTypeString(V);
 
   return "ERROR in cling's callPrintValue(): missing value string.";
 }

test/Prompt/ValuePrinter/Regression.C

@@ -90,6 +90,7 @@ auto bla=[](double *x, double *par, int blub){return x[0]*blub;} // CHECK: ((lam
 #include <functional>
 using namespace std::placeholders;
 auto fn_moo = std::bind (bla, _1,_2,10) // CHECK: ERROR in cling's callPrintValue(): missing value string.
+// expected-error {{Could not execute cling::printValue with '{{.*}}'}}
 // expected-error {{use of undeclared identifier 'lambda'}}
 // expected-error {{expected expression}}
 // expected-error {{type name requires a specifier or qualifier}}