resurrect and improve loplugin:referencecasting

Improve the plugin to avoid generating false+ with the special case of
querying XInterface (what the code calls normalisation).

Also ignore places where the querying is dealing with ambiguous base
classes.

Change-Id: I23b2b2fa6618328fafc4707b94c26582a462ea87
Reviewed-on: https://gerrit.libreoffice.org/74993
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

2 files changed, 0 insertions, 228 deletions

diff --git a/compilerplugins/clang/store/referencecasting.cxx b/compilerplugins/clang/store/referencecasting.cxx
deleted file mode 100644
index ed74b0b6e14a..000000000000
--- a/compilerplugins/clang/store/referencecasting.cxx
+++ /dev/null
@@ -1,195 +0,0 @@
-/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
-/*
- * This file is part of the LibreOffice project.
- *
- * Based on LLVM/Clang.
- *
- * This file is distributed under the University of Illinois Open Source
- * License. See LICENSE.TXT for details.
- *
- */
-
-#include "referencecasting.hxx"
-
-#include <clang/AST/Attr.h>
-#include <iostream>
-
-namespace loplugin
-{
-
-/*
-This is a compile-time checker.
-
-Check for cases where we have
- - two IDL interfaces A and B,
- - B extends A
- - we are converting a Reference<B> to a Reference<A>
-
-Note that it generates the occasional false positive.
-
-Also, it makes clang3.2 crash on about 4 files in the LO codebase.
-I have logged a bug here:
-  http://llvm.org/bugs/show_bug.cgi?id=15902
-
-*/
-ReferenceCasting::ReferenceCasting( CompilerInstance& compiler )
-    : FilteringPlugin( compiler )
-{
-}
-
-void ReferenceCasting::run()
-{
-    TraverseDecl( compiler.getASTContext().getTranslationUnitDecl());
-}
-
-// This:
-// static void example_method()
-// {
-//     css::uno::Reference<B> b;
-//     css::uno::Reference<A>(b, css::uno::UNO_QUERY);
-// }
-// Compiles to this AST:
-// (CompoundStmt 0x205d430 </noel-extra1/libo-clang/compilerplugins/clang/noel1.cxx:17:1, line:20:1>
-//   (DeclStmt 0x20580a8 <line:18:5, col:32>
-//     (0x20530e0 "css::uno::Reference<B> refB =
-//       (CXXConstructExpr 0x2058078 <col:28> 'css::uno::Reference<B>':'class com::sun::star::uno::Reference<class B>''void(void)')"))
-//   (DeclStmt 0x205d418 <line:19:5, col:59>
-//     (0x2058310 "css::uno::Reference<A> refA =
-//       (CXXConstructExpr 0x205d3d8 <col:28, col:58> 'css::uno::Reference<A>':'class com::sun::star::uno::Reference<class A>''void (const class com::sun::star::uno::BaseReference &, enum com::sun::star::uno::UnoReference_Query)'
-//         (ImplicitCastExpr 0x205d3c0 <col:33> 'const class com::sun::star::uno::BaseReference' lvalue <NoOp>
-//           (ImplicitCastExpr 0x205d3a0 <col:33> 'class com::sun::star::uno::BaseReference' lvalue <DerivedToBase (BaseReference)>
-//             (DeclRefExpr 0x20582a0 <col:33> 'css::uno::Reference<B>':'class com::sun::star::uno::Reference<class B>' lvalue Var 0x20530e0 'refB' 'css::uno::Reference<B>':'class com::sun::star::uno::Reference<class B>')))
-//         (DeclRefExpr 0x2058398 <col:39, col:49> 'enum com::sun::star::uno::UnoReference_Query' EnumConstant 0x1831de0 'UNO_QUERY' 'enum com::sun::star::uno::UnoReference_Query'))")))
-//
-//
-// This:
-// static void example_method1(css::uno::Reference<A>)
-// {
-// }
-// static void example_method2()
-// {
-//     css::uno::Reference<B> refB;
-//     example_method1(css::uno::Reference<A>(refB, css::uno::UNO_QUERY));
-// }
-//  Compiles to this AST:
-// static void example_method1(css::uno::Reference<A>) (CompoundStmt 0x2a74ee8 </noel-extra1/libo-clang/compilerplugins/clang/noel1.cxx:17:1, line:18:1>)
-// static void example_method2() (CompoundStmt 0x2a7a650 </noel-extra1/libo-clang/compilerplugins/clang/noel1.cxx:21:1, line:24:1>
-//  (DeclStmt 0x2a7a1a8 <line:22:5, col:32>
-//    (0x2a751e0 "css::uno::Reference<B> refB =
-//      (CXXConstructExpr 0x2a7a178 <col:28> 'css::uno::Reference<B>':'class com::sun::star::uno::Reference<class B>''void(void)')"))
-//  (ExprWithCleanups 0x2a7a638 <line:23:5, col:70> 'void'
-//    (CallExpr 0x2a7a570 <col:5, col:70> 'void'
-//      (ImplicitCastExpr 0x2a7a558 <col:5> 'void (*)(css::uno::Reference<A>)' <FunctionToPointerDecay>
-//        (DeclRefExpr 0x2a7a4d8 <col:5> 'void (css::uno::Reference<A>)' lvalue Function 0x2a6ff00 'example_method1' 'void (css::uno::Reference<A>)'))
-//      (CXXBindTemporaryExpr 0x2a7a618 <col:21, col:69> 'css::uno::Reference<A>':'class com::sun::star::uno::Reference<class A>' (CXXTemporary 0x2a7a610)
-//        (CXXConstructExpr 0x2a7a5d8 <col:21, col:69> 'css::uno::Reference<A>':'class com::sun::star::uno::Reference<class A>''void (const Reference<class A> &)' elidable
-//          (MaterializeTemporaryExpr 0x2a7a5c0 <col:21, col:69> 'const Reference<class A>':'const class com::sun::star::uno::Reference<class A>' lvalue
-//            (ImplicitCastExpr 0x2a7a5a8 <col:21, col:69> 'const Reference<class A>':'const class com::sun::star::uno::Reference<class A>' <NoOp>
-//              (CXXBindTemporaryExpr 0x2a7a4b8 <col:21, col:69> 'css::uno::Reference<A>':'class com::sun::star::uno::Reference<class A>' (CXXTemporary 0x2a7a4b0)
-//                (CXXTemporaryObjectExpr 0x2a7a460 <col:21, col:69> 'css::uno::Reference<A>':'class com::sun::star::uno::Reference<class A>''void (const class com::sun::star::uno::BaseReference &, enum com::sun::star::uno::UnoReference_Query)'
-//                  (ImplicitCastExpr 0x2a7a448 <col:44> 'const class com::sun::star::uno::BaseReference' lvalue <NoOp>
-//                    (ImplicitCastExpr 0x2a7a428 <col:44> 'class com::sun::star::uno::BaseReference' lvalue <DerivedToBase (BaseReference)>
-//                      (DeclRefExpr 0x2a7a340 <col:44> 'css::uno::Reference<B>':'class com::sun::star::uno::Reference<class B>' lvalue Var 0x2a751e0 'refB' 'css::uno::Reference<B>':'class com::sun::star::uno::Reference<class B>')))
-//                  (DeclRefExpr 0x2a7a398 <col:50, col:60> 'enum com::sun::star::uno::UnoReference_Query' EnumConstant 0x224ee20 'UNO_QUERY' 'enum com::sun::star::uno::UnoReference_Query'))))))))))
-
-static const Type* extractTemplateType(Expr* cce);
-
-bool ReferenceCasting::VisitCXXConstructExpr( CXXConstructExpr* cce )
-{
-    // don't bother processing anything in the Reference.h file. Makes my life easier when debugging this.
-    if( StringRef(compiler.getSourceManager().getPresumedLoc( cce->getSourceRange().getBegin() )).find( "Reference.h" ) != StringRef::npos )
-        return true;
-
-    // look for calls to the Reference<T>(x,UNO_something) constructor
-    if( cce->getConstructor()->getNameInfo().getName().getAsString() != "Reference" )
-        return true;
-
-    if( cce->getNumArgs() != 2 )
-        return true;
-
-    // extract the type parameter passed to the template
-    const Type * templateParamType = extractTemplateType(cce);
-    if ( !templateParamType )
-        return true;
-
-    // extract the type of the first parameter passed to the constructor
-    Expr* constructorArg0 = cce->getArg(0);
-    if( !constructorArg0 )
-       return true;
-
-    // ignore the Reference(XInterface*,...) constructor
-    if( constructorArg0->getType()->isPointerType() )
-       return true;
-
-    // drill down the expression tree till we hit the bottom
-    DeclRefExpr* constructorSubArg2;
-    Expr* constructorArg0SubExpr = constructorArg0;
-    for(;;)
-    {
-        // if we've hit the member expression we want, break
-        constructorSubArg2 = dyn_cast<DeclRefExpr>( constructorArg0SubExpr );
-        if( constructorSubArg2 )
-            break;
-        CastExpr* tmp1 = dyn_cast<CastExpr>( constructorArg0SubExpr );
-        if( tmp1 ) {
-            constructorArg0SubExpr = tmp1->getSubExpr();
-            continue;
-        }
-        MaterializeTemporaryExpr* tmp2 = dyn_cast<MaterializeTemporaryExpr>( constructorArg0SubExpr );
-        if( tmp2 ) {
-            constructorArg0SubExpr = tmp2->GetTemporaryExpr();
-            continue;
-        }
-        CXXBindTemporaryExpr* tmp3 = dyn_cast<CXXBindTemporaryExpr>( constructorArg0SubExpr );
-        if( tmp3 ) {
-            constructorArg0SubExpr = tmp3->getSubExpr();
-            continue;
-        }
-        CXXTemporaryObjectExpr* tmp4 = dyn_cast<CXXTemporaryObjectExpr>( constructorArg0SubExpr );
-        if( tmp4 ) {
-            constructorArg0SubExpr = tmp4->getArg(0);
-            continue;
-        }
-        return true;
-    }
-
-    const Type * tmp3 = extractTemplateType( constructorSubArg2 );
-    if ( !tmp3 )
-        return true;
-
-    const RecordType* templateParamRT = dyn_cast<RecordType>( templateParamType );
-    const RecordType* constructorArgRT = dyn_cast<RecordType>( tmp3 );
-    if( !templateParamRT || !constructorArgRT )
-       return true;
-
-    CXXRecordDecl* templateParamRD = dyn_cast<CXXRecordDecl>( templateParamRT->getDecl() );
-    CXXRecordDecl* constructorArgRD = dyn_cast<CXXRecordDecl>( constructorArgRT->getDecl() );
-
-    if (constructorArgRD->Equals(templateParamRD) || constructorArgRD->isDerivedFrom(templateParamRD))
-        report( DiagnosticsEngine::Warning,
-                "the source reference is already a subtype of the destination reference",
-                cce->getLocStart()) // and the exact position where the message should point
-                    << cce->getSourceRange(); // and the full return statement to highlight (optional)
-
-    return true;
-}
-
-static const Type* extractTemplateType(Expr* cce)
-{
-    QualType cceQT = cce->getType();
-    const Type* cceType = cceQT.getTypePtr();
-    const TemplateSpecializationType* cceTST = dyn_cast<TemplateSpecializationType>( cceType );
-    if( !cceTST )
-        return NULL;
-    if( cceTST->getNumArgs() != 1 )
-        return NULL;
-    const TemplateArgument & cceTA = cceTST->getArg(0);
-    QualType templateParamQT = cceTA.getAsType();
-    return templateParamQT.getTypePtr();
-}
-
-static Plugin::Registration< ReferenceCasting > X( "referencecasting" );
-
-} // namespace
-
-/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/compilerplugins/clang/store/referencecasting.hxx b/compilerplugins/clang/store/referencecasting.hxx
deleted file mode 100644
index 3c41b773e0f0..000000000000
--- a/compilerplugins/clang/store/referencecasting.hxx
+++ /dev/null
@@ -1,33 +0,0 @@
-/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
-/*
- * This file is part of the LibreOffice project.
- *
- * Based on LLVM/Clang.
- *
- * This file is distributed under the University of Illinois Open Source
- * License. See LICENSE.TXT for details.
- *
- */
-
-#ifndef REFERENCECASTING_H
-#define REFERENCECASTING_H
-
-#include "plugin.hxx"
-
-namespace loplugin
-{
-
-class ReferenceCasting
-    : public FilteringPlugin< ReferenceCasting >
-    {
-    public:
-        explicit ReferenceCasting( CompilerInstance& compiler );
-        virtual void run() override;
-        bool VisitCXXConstructExpr( CXXConstructExpr* cce );
-    };
-
-} // namespace
-
-#endif // REFERENCECASTING_H
-
-/* vim:set shiftwidth=4 softtabstop=4 expandtab: */