1 files changed, 31 insertions, 20 deletions

diff --git a/compilerplugins/clang/casttovoid.cxx b/compilerplugins/clang/casttovoid.cxx
index 1717fa09a516..4026162ea0c1 100644
--- a/compilerplugins/clang/casttovoid.cxx
+++ b/compilerplugins/clang/casttovoid.cxx
@@ -20,20 +20,6 @@
 
 namespace {
 
-bool isWarnUnusedType(QualType type) {
-    if (auto const t = type->getAs<TypedefType>()) {
-        if (t->getDecl()->hasAttr<WarnUnusedAttr>()) {
-            return true;
-        }
-    }
-    if (auto const t = type->getAs<RecordType>()) {
-        if (t->getDecl()->hasAttr<WarnUnusedAttr>()) {
-            return true;
-        }
-    }
-    return loplugin::isExtraWarnUnusedType(type);
-}
-
 Expr const * lookThroughInitListExpr(Expr const * expr) {
     if (auto const ile = dyn_cast<InitListExpr>(expr->IgnoreParenImpCasts())) {
         if (ile->getNumInits() == 1) {
@@ -203,6 +189,9 @@ public:
         if (var == nullptr) {
             return true;
         }
+        if (var->getType().isVolatileQualified()) {
+            return true;
+        }
         auto & usage = vars_[var->getCanonicalDecl()];
         if (!castToVoid_.empty() && castToVoid_.top().sub == expr) {
             usage.castToVoid.push_back(castToVoid_.top().cast);
@@ -423,6 +412,11 @@ private:
                     }
                 }
             } else {
+                if (auto const fun = dyn_cast_or_null<FunctionDecl>(i.first->getDeclContext())) {
+                    if (containsPreprocessingConditionalInclusion(fun->getSourceRange())) {
+                        continue;
+                    }
+                }
                 for (auto const j: i.second.castToVoid) {
                     report(
                         DiagnosticsEngine::Warning, "unnecessary cast to void",
@@ -437,12 +431,26 @@ private:
         }
     }
 
+    bool isWarnUnusedType(QualType type) {
+        if (auto const t = type->getAs<TypedefType>()) {
+            if (t->getDecl()->hasAttr<WarnUnusedAttr>()) {
+                return true;
+            }
+        }
+        if (auto const t = type->getAs<RecordType>()) {
+            if (compat::getDefinitionOrSelf(compat::getDecl(t))->hasAttr<WarnUnusedAttr>()) {
+                return true;
+            }
+        }
+        return loplugin::isExtraWarnUnusedType(compiler.getASTContext(), type);
+    }
+
     bool isFromCIncludeFile(SourceLocation spellingLocation) const {
         return !compiler.getSourceManager().isInMainFile(spellingLocation)
-            && (StringRef(
-                    compiler.getSourceManager().getPresumedLoc(spellingLocation)
-                    .getFilename())
-                .endswith(".h"));
+            && compat::ends_with(
+                StringRef(
+                    compiler.getSourceManager().getPresumedLoc(spellingLocation).getFilename()),
+                ".h");
     }
 
     bool isSharedCAndCppCode(VarDecl const * decl) const {
@@ -464,7 +472,7 @@ private:
             return nullptr;
         }
         if (compiler.getSourceManager().isMacroBodyExpansion(
-                compat::getBeginLoc(expr)))
+                expr->getBeginLoc()))
         {
             return nullptr;
         }
@@ -507,11 +515,14 @@ private:
         if (var == nullptr) {
             return;
         }
+        if (var->getType().isVolatileQualified()) {
+            return;
+        }
         auto & usage = vars_[var->getCanonicalDecl()];
         if (usage.firstConsumption != nullptr) {
             return;
         }
-        auto const loc = compat::getBeginLoc(dre);
+        auto const loc = dre->getBeginLoc();
         if (compiler.getSourceManager().isMacroArgExpansion(loc)
             && (Lexer::getImmediateMacroNameForDiagnostics(
                     loc, compiler.getSourceManager(), compiler.getLangOpts())