[cpp] Invalid code on switch with enum from callable

[tobil4sk]

Regression in #11151

https://github.com/HaxeCheckstyle/tokentree/blob/d6f75b95d037aafe1dbc97cf77352f37c0c74ff3/src/tokentree/TokenTree.hx#L119

Error: ./src/tokentree/TokenTree.cpp: In member function ‘void tokentree::TokenTree_obj::internalFilterCallback(hx::Callable<hx::ObjectPtr<tokentree::FilterResult_obj>(hx::ObjectPtr<tokentree::TokenTree_obj>, int)>, Array<Dynamic>, Dynamic)’:
./src/tokentree/TokenTree.cpp:551:90: error: ‘class hx::ObjectPtr<tokentree::FilterResult_obj>’ has no member named ‘StaticCast’
  551 | HXLINE( 119)                    switch((int)(callback(::hx::ObjectPtr<OBJ_>(this),depth).StaticCast< ::hx::EnumBase >()->_hx_getIndex())){
      |                                                                                          ^~~~~~~~~~
./src/tokentree/TokenTree.cpp:551:117: error: expected primary-expression before ‘>’ token
  551 | HXLINE( 119)                    switch((int)(callback(::hx::ObjectPtr<OBJ_>(this),depth).StaticCast< ::hx::EnumBase >()->_hx_getIndex())){
      |                                                                                                                     ^
./src/tokentree/TokenTree.cpp:551:119: error: expected primary-expression before ‘)’ token
  551 | HXLINE( 119)                    switch((int)(callback(::hx::ObjectPtr<OBJ_>(this),depth).StaticCast< ::hx::EnumBase >()->_hx_getIndex())){
      |                                                                                                                       ^
At global scope:
cc1plus: note: unrecognized command-line option ‘-Wno-inconsistent-missing-override’ may have been intended to silence earlier diagnostics

Stripped down sample:

enum E {
	A;
	B;
}

function main() {
	final callback:() -> E = () -> cast null;
	trace(callback().match(A));
}

Error: ./src/_Main/Main_Fields_.cpp: In static member function ‘static void _Main::Main_Fields__obj::main()’:
./src/_Main/Main_Fields_.cpp:69:41: error: ‘class hx::ObjectPtr<E_obj>’ has no member named ‘StaticCast’
   69 | HXDLIN(   8)            if ((callback().StaticCast< ::hx::EnumBase >()->_hx_getIndex() == 0)) {
      |                                         ^~~~~~~~~~
./src/_Main/Main_Fields_.cpp:69:68: error: expected primary-expression before ‘>’ token
   69 | HXDLIN(   8)            if ((callback().StaticCast< ::hx::EnumBase >()->_hx_getIndex() == 0)) {
      |                                                                    ^
./src/_Main/Main_Fields_.cpp:69:70: error: expected primary-expression before ‘)’ token
   69 | HXDLIN(   8)            if ((callback().StaticCast< ::hx::EnumBase >()->_hx_getIndex() == 0)) {
      |                                                                      ^

Seems like it should be generating callback()->_hx_getIndex() instead of callback().StaticCast< ::hx::EnumBase >()->_hx_getIndex(), since it's not dynamic anymore.

[tobil4sk]

@Aidan63 thanks for looking into it! With your patch my original program is compiling fine, and so is formatter.

However, I don't think the test case is actually covering it since the callable result is a regular function argument, not a switch/match. Without your patch it generated this, which still compiled fine for me:

HXLINE(  14)		 ::unit::issues::_Issue12586::E _hx_tmp = ::hx::Callable<  ::unit::issues::_Issue12586::E() >(new _hx_Closure_0())();
HXDLIN(  14)		this->eq(::unit::issues::_Issue12586::E_obj::A_dyn(),_hx_tmp,::hx::SourceInfo(HX_("src/unit/issues/Issue12586.hx",70,95,dc,a1),14,HX_("unit.issues.Issue12586",e3,fe,eb,77),HX_("test",52,c8,f9,4c)));

I think we need a test case like this, with an explicit match or switch expression:

t(callback().match(A));

I was going to open a PR to add it, but when I added that test the error came back. I was confused because it's the same as my original sample. It turns out, the unit tests are using -D analyzer-optimize, and if I add that it also brings it back:

	::hx::Callable< void ( ::Dynamic, ::Dynamic) > _hx_tmp = ::haxe::Log_obj::trace;
	bool _hx_tmp1;
	if ((::hx::Callable<  ::_Main::E() >(new _hx_Closure_0())().StaticCast< ::hx::EnumBase >()->_hx_getIndex() == 0)) {
		_hx_tmp1 = true;
	}
	else {
		_hx_tmp1 = false;
	}
	_hx_tmp(_hx_tmp1,::hx::SourceInfo(HX_("Main.hx",05,5c,7e,08),9,HX_("Main",59,64,2f,33),HX_("main",39,38,56,48)));

[tobil4sk]

@Simn would you mind reopening this? I don't have permission to.

TLDR is that the error is still present when compiling the sample with -D analyzer-optimize

[Aidan63]

I've got a proper fix for this now (https://github.com/Aidan63/haxe/tree/cpp-enum-callable) and have updated that test. I'm just working on fixing one failing cppia test (Issue6560)

[Aidan63]

Should be properly fixed now.

[tobil4sk]

Seems like it works now with -D analyzer-optimize, but it is broken again with the analyzer disabled... 😅

The formatter benchmarks are still failing to build.

Could we reopen?

[tobil4sk]

@Aidan63 thanks! Formatter cpp benchmarks are back now