Avoid checking if a function uses itself as function pointer

src/arduino.cc/builder/ctags/ctags_to_prototypes.go

@@ -56,32 +56,32 @@ func (p *CTagsParser) findLineWhereToInsertPrototypes() int {
 }
 
 func (p *CTagsParser) firstFunctionPointerUsedAsArgument() int {
-	functionNames := p.collectFunctionNames()
+	functionTags := p.collectFunctions()
 	for _, tag := range p.tags {
-		if functionNameUsedAsFunctionPointerIn(tag, functionNames) {
+		if functionNameUsedAsFunctionPointerIn(tag, functionTags) {
 			return tag.Line
 		}
 	}
 	return -1
 }
 
-func functionNameUsedAsFunctionPointerIn(tag *types.CTag, functionNames []string) bool {
-	for _, functionName := range functionNames {
-		if strings.Index(tag.Code, "&"+functionName) != -1 {
+func functionNameUsedAsFunctionPointerIn(tag *types.CTag, functionTags []*types.CTag) bool {
+	for _, functionTag := range functionTags {
+		if tag.Line != functionTag.Line && strings.Index(tag.Code, "&"+functionTag.FunctionName) != -1 {
 			return true
 		}
 	}
 	return false
 }
 
-func (p *CTagsParser) collectFunctionNames() []string {
-	names := []string{}
+func (p *CTagsParser) collectFunctions() []*types.CTag {
+	functionTags := []*types.CTag{}
 	for _, tag := range p.tags {
 		if tag.Kind == KIND_FUNCTION {
-			names = append(names, tag.FunctionName)
+			functionTags = append(functionTags, tag)
 		}
 	}
-	return names
+	return functionTags
 }
 
 func (p *CTagsParser) firstFunctionAtLine() int {

src/arduino.cc/builder/test/sketch_with_fake_function_pointer/sketch_with_fake_function_pointer.ino

@@ -0,0 +1,19 @@
+template< uint16_t nBuffSize >
+  class Foo{
+    public: 
+
+    template< uint16_t N >
+      Foo &operator +=( const Foo<N> &ref ){
+        //...
+        return *this;
+    }
+};
+
+Foo<64> a;
+Foo<32> b;
+
+void setup(){
+  a += b;
+}
+
+void loop(){}

src/arduino.cc/builder/test/try_build_of_problematic_sketch_test.go

@@ -205,6 +205,10 @@ func TestTryBuild039(t *testing.T) {
 	tryBuildWithContext(t, ctx, "sketch12", "sketch12.ino")
 }
 
+func TestTryBuild040(t *testing.T) {
+	tryBuild(t, "sketch_with_fake_function_pointer", "sketch_with_fake_function_pointer.ino")
+}
+
 func makeDefaultContext(t *testing.T) *types.Context {
 	DownloadCoresAndToolsAndLibraries(t)