loplugin:passstuffbyref even more return improvements

Change-Id: I2a752025cd429e4d271626402dce5d8a8b0c76d2
Reviewed-on: https://gerrit.libreoffice.org/47021
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

2 files changed, 15 insertions, 1 deletions

diff --git a/compilerplugins/clang/passstuffbyref.cxx b/compilerplugins/clang/passstuffbyref.cxx
index 98b75abac960..0630beb80b59 100644
--- a/compilerplugins/clang/passstuffbyref.cxx
+++ b/compilerplugins/clang/passstuffbyref.cxx
@@ -229,6 +229,10 @@ void PassStuffByRef::checkReturnValue(const FunctionDecl * functionDecl, const C
         return;
     }
 
+    // not sure if it's possible to modify these
+    if (isa<CXXConversionDecl>(functionDecl))
+        return;
+
     // ignore stuff that forms part of the stable URE interface
     if (isInUnoIncludeFile(functionDecl)) {
         return;
@@ -267,6 +271,9 @@ void PassStuffByRef::checkReturnValue(const FunctionDecl * functionDecl, const C
     if (startswith(type.getAsString(), "struct o3tl::strong_int")) {
         return;
     }
+
+    //functionDecl->dump();
+
     mbInsideFunctionDecl = true;
     mbFoundReturnValueDisqualifier = false;
     TraverseStmt(functionDecl->getBody());
@@ -395,7 +402,9 @@ bool PassStuffByRef::isReturnExprDisqualified(const Expr* expr)
             FunctionDecl const * calleeFunctionDecl = callExpr->getDirectCallee();
             if (!calleeFunctionDecl)
                 return true;
-            return !loplugin::TypeCheck(calleeFunctionDecl->getReturnType()).LvalueReference();
+            auto tc = loplugin::TypeCheck(calleeFunctionDecl->getReturnType());
+            if (!tc.LvalueReference() && !tc.Pointer())
+                return true;
         }
         return false;
     }
diff --git a/compilerplugins/clang/test/passstuffbyref.cxx b/compilerplugins/clang/test/passstuffbyref.cxx
index 3178bf7329f2..99e4a5a189b6 100644
--- a/compilerplugins/clang/test/passstuffbyref.cxx
+++ b/compilerplugins/clang/test/passstuffbyref.cxx
@@ -9,6 +9,7 @@
 
 #include <rtl/ustring.hxx>
 #include <sys/time.h>
+#include <o3tl/cow_wrapper.hxx>
 #include <vector>
 
 struct S1 {
@@ -21,6 +22,7 @@ struct S2 {
     OUString mv3[2];
     S1 child;
     static OUString gs1;
+    o3tl::cow_wrapper<S1> mxCow;
 
     // make sure we ignore cases where the passed in parameter is std::move'd
     S2(OUString v1, OUString v2)
@@ -35,6 +37,9 @@ struct S2 {
     OUString get7() { return get6(); } // expected-error {{rather return class rtl::OUString by const& than by value, to avoid unnecessary copying [loplugin:passstuffbyref]}}
     OUString & get8() { return gs1; }
     OUString get9() { return get8(); } // expected-error {{rather return class rtl::OUString by const& than by value, to avoid unnecessary copying [loplugin:passstuffbyref]}}
+    // TODO
+    OUString get10() { return OUString(*&get6()); } // todoexpected-error {{rather return class rtl::OUString by const& than by value, to avoid unnecessary copying [loplugin:passstuffbyref]}}
+    OUString get11() const { return mxCow->get(); } // expected-error {{rather return class rtl::OUString by const& than by value, to avoid unnecessary copying [loplugin:passstuffbyref]}}
 
     // no warning expected
     OUString set1() { return OUString("xxx"); }