Improve loplugin:redundantpointerops diagnostic messages

Change-Id: If09f5c916f2db98c5d1754d2fbc8f53c502799c9
Reviewed-on: https://gerrit.libreoffice.org/80543
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

3 files changed, 28 insertions, 10 deletions

diff --git a/compilerplugins/clang/compat.hxx b/compilerplugins/clang/compat.hxx
index cb13f44cfa66..c091c51601f7 100644
--- a/compilerplugins/clang/compat.hxx
+++ b/compilerplugins/clang/compat.hxx
@@ -240,6 +240,19 @@ inline const clang::Expr *getSubExprAsWritten(const clang::CastExpr *This) {
   return getSubExprAsWritten(const_cast<clang::CastExpr *>(This));
 }
 
+inline clang::QualType getObjectType(clang::CXXMemberCallExpr const * expr) {
+#if CLANG_VERSION >= 100000
+    return expr->getObjectType();
+#else
+    // <https://github.com/llvm/llvm-project/commit/88559637641e993895337e1047a0bd787fecc647>
+    // "[OpenCL] Improve destructor support in C++ for OpenCL":
+    clang::QualType Ty = expr->getImplicitObjectArgument()->getType();
+    if (Ty->isPointerType())
+        Ty = Ty->getPointeeType();
+    return Ty;
+#endif
+}
+
 inline bool isExplicitSpecified(clang::CXXConstructorDecl const * decl) {
 #if CLANG_VERSION >= 90000
     return decl->getExplicitSpecifier().isExplicit();
diff --git a/compilerplugins/clang/redundantpointerops.cxx b/compilerplugins/clang/redundantpointerops.cxx
index 5406989696c5..dbb3ef7882fd 100644
--- a/compilerplugins/clang/redundantpointerops.cxx
+++ b/compilerplugins/clang/redundantpointerops.cxx
@@ -75,8 +75,10 @@ bool RedundantPointerOps::VisitMemberExpr(MemberExpr const * memberExpr)
         {
             if (unaryOp->getOpcode() == UO_AddrOf)
                 report(
-                    DiagnosticsEngine::Warning, "'&' followed by '->', rather use '.'",
+                    DiagnosticsEngine::Warning,
+                    "'&' followed by '->' operating on %0, rather use '.'",
                     compat::getBeginLoc(memberExpr))
+                    << memberExpr->getBase()->getType()->getPointeeType()
                     << memberExpr->getSourceRange();
 
         }
@@ -84,8 +86,10 @@ bool RedundantPointerOps::VisitMemberExpr(MemberExpr const * memberExpr)
         {
             if (operatorCallExpr->getOperator() == OO_Amp)
                 report(
-                    DiagnosticsEngine::Warning, "'&' followed by '->', rather use '.'",
+                    DiagnosticsEngine::Warning,
+                    "'&' followed by '->' operating on %0, rather use '.'",
                     compat::getBeginLoc(memberExpr))
+                    << memberExpr->getBase()->getType()->getPointeeType()
                     << memberExpr->getSourceRange();
 
         }
@@ -117,9 +121,9 @@ bool RedundantPointerOps::VisitUnaryOperator(UnaryOperator const * unaryOperator
     auto innerOp = dyn_cast<UnaryOperator>(subExpr);
     if (innerOp && innerOp->getOpcode() == UO_AddrOf)
         report(
-            DiagnosticsEngine::Warning, "'&' followed by '*', rather use '.'",
+            DiagnosticsEngine::Warning, "'&' followed by '*' operating on %0, rather use '.'",
             compat::getBeginLoc(unaryOperator))
-            << unaryOperator->getSourceRange();
+            << innerOp->getSubExpr()->getType() << unaryOperator->getSourceRange();
     if (auto cxxMemberCallExpr = dyn_cast<CXXMemberCallExpr>(subExpr))
     {
         auto methodDecl = cxxMemberCallExpr->getMethodDecl();
@@ -128,9 +132,10 @@ bool RedundantPointerOps::VisitUnaryOperator(UnaryOperator const * unaryOperator
             auto className = cxxMemberCallExpr->getRecordDecl()->getName();
             if (className == "unique_ptr" || className == "shared_ptr" || className == "Reference" || className == "SvRef")
                 report(
-                    DiagnosticsEngine::Warning, "'*' followed by '.get()', just use '*'",
+                    DiagnosticsEngine::Warning,
+                    "'*' followed by '.get()' operating on %0, just use '*'",
                     compat::getBeginLoc(unaryOperator))
-                    << unaryOperator->getSourceRange();
+                    << compat::getObjectType(cxxMemberCallExpr) << unaryOperator->getSourceRange();
 
         }
     }
diff --git a/compilerplugins/clang/test/redundantpointerops.cxx b/compilerplugins/clang/test/redundantpointerops.cxx
index 30c22b02614f..0a1f7b3afad5 100644
--- a/compilerplugins/clang/test/redundantpointerops.cxx
+++ b/compilerplugins/clang/test/redundantpointerops.cxx
@@ -15,7 +15,7 @@ struct Struct1 {
 
 void function1(Struct1& s)
 {
-    (&s)->x = 1; // expected-error {{'&' followed by '->', rather use '.' [loplugin:redundantpointerops]}}
+    (&s)->x = 1; // expected-error {{'&' followed by '->' operating on 'Struct1', rather use '.' [loplugin:redundantpointerops]}}
 };
 
 struct Struct2 {
@@ -25,12 +25,12 @@ struct Struct2 {
 
 void function2(Struct2 s)
 {
-    (&s)->x = 1; // expected-error {{'&' followed by '->', rather use '.' [loplugin:redundantpointerops]}}
+    (&s)->x = 1; // expected-error {{'&' followed by '->' operating on 'Struct2', rather use '.' [loplugin:redundantpointerops]}}
 };
 
 void function3(Struct1& s)
 {
-    (*(&s)).x = 1; // expected-error {{'&' followed by '*', rather use '.' [loplugin:redundantpointerops]}}
+    (*(&s)).x = 1; // expected-error {{'&' followed by '*' operating on 'Struct1', rather use '.' [loplugin:redundantpointerops]}}
 };
 
 //void function4(Struct1* s)
@@ -40,7 +40,7 @@ void function3(Struct1& s)
 
 int function5(std::unique_ptr<int> x)
 {
-    return *x.get(); // expected-error {{'*' followed by '.get()', just use '*' [loplugin:redundantpointerops]}}
+    return *x.get(); // expected-error-re {{'*' followed by '.get()' operating on '{{.*}}unique_ptr{{.*}}', just use '*' [loplugin:redundantpointerops]}}
 };