Compiler crashing when Main.create has an undefined method

[winksaville]

The code below and here on playground crashes the compiler:

type Children is (Child1 | Child2)

class Parent
  let env: Env
  var child1: (Child1 | None) = None
  var child2: (Child2 | None) = None
  var cur_data: (Children | None) = None

  new create(env': Env) =>
    env = env'
    child1 = Child1(this)
    child2 = Child2(this)
    change(child1)


  fun ref change(child: Children) =>
    cur_data = child

  fun ref doIt() =>
    match cur_data
    | let c: Children => c.doIt()
    end


class Child1
  let _parent: Parent

  new create(parent: Parent ref) =>
    _parent = parent

  fun getParent(): this->Parent =>
    _parent

  fun doIt() =>
    _parent.env.out.print("Child1.doIt()")



class Child2
  let _parent: Parent

  new create(parent: Parent ref) =>
    _parent = parent

  fun getParent(): this->Parent =>
    _parent

  fun doIt() =>
    _parent.env.out.print("Child2.doIt()")


actor Main
  var data: Parent

  new create(env: Env) =>
    data = Parent(env)
    doit()

  be doIt() =>
    data.doIt()

Here is the stack trace:

$ ponyc .
Building builtin -> /usr/local/lib/pony/0.21.3-42b521798/packages/builtin
Building . -> /home/wink/prgs/pony/parent-child-initialization
src/libponyc/pass/refer.c:228: suggest_alt_name: Assertion `ast_id(id) == TK_ID` failed.

Backtrace:
  ponyc(ponyint_assert_fail+0xf1) [0x55ceec6c93b1]
  ponyc(+0x6961f) [0x55ceec5f961f]
  ponyc(refer_reference+0xb9) [0x55ceec5f9821]
  ponyc(pass_refer+0x6f) [0x55ceec5fc484]
  ponyc(ast_visit+0x279) [0x55ceec5e0d36]
  ponyc(ast_visit+0x1c5) [0x55ceec5e0c82]
  ponyc(ast_visit+0x1c5) [0x55ceec5e0c82]
  ponyc(ast_visit+0x1c5) [0x55ceec5e0c82]
  ponyc(ast_visit+0x1c5) [0x55ceec5e0c82]
  ponyc(ast_visit+0x1c5) [0x55ceec5e0c82]
  ponyc(ast_visit+0x1c5) [0x55ceec5e0c82]
  ponyc(ast_visit+0x1c5) [0x55ceec5e0c82]
  ponyc(ast_visit+0x1c5) [0x55ceec5e0c82]
  ponyc(+0x50341) [0x55ceec5e0341]
  ponyc(+0x506d4) [0x55ceec5e06d4]
  ponyc(ast_passes_program+0x28) [0x55ceec5e089c]
  ponyc(program_load+0xc1) [0x55ceec637648]
  ponyc(+0x4fc34) [0x55ceec5dfc34]
  ponyc(main+0x19c) [0x55ceec5dfe65]
  /usr/lib/libc.so.6(__libc_start_main+0xea) [0x7f1f41c77f4a]
  ponyc(_start+0x2a) [0x55ceec5dfaaa]
Aborted (core dumped)

This is from a debug version of current master as of today:

$ ponyc --version
0.21.3-42b521798 [debug]
compiled with: llvm 5.0.1 -- cc (GCC) 7.2.1 20171224
Defaults: pic=true openssl=openssl_1.1.0

I'll be working on getting it to compile and updating this issue as I learn more.

[winksaville]

So here is a simpler version that crashes the compiler, the problem is I misspelled doIt():

actor Main
  new create(env: Env) =>
    doit() // crash compiler
    //doIt() // OK

  be doIt() =>
    None

Here is the crash

$ ponyc .
Building builtin -> /usr/local/lib/pony/0.21.3-42b521798/packages/builtin
Building . -> /home/wink/prgs/pony/parent-child-initialization
src/libponyc/pass/refer.c:228: suggest_alt_name: Assertion `ast_id(id) == TK_ID` failed.

Backtrace:
  ponyc(ponyint_assert_fail+0xf1) [0x561282b343b1]
  ponyc(+0x6961f) [0x561282a6461f]
  ponyc(refer_reference+0xb9) [0x561282a64821]
  ponyc(pass_refer+0x6f) [0x561282a67484]
  ponyc(ast_visit+0x279) [0x561282a4bd36]
  ponyc(ast_visit+0x1c5) [0x561282a4bc82]
  ponyc(ast_visit+0x1c5) [0x561282a4bc82]
  ponyc(ast_visit+0x1c5) [0x561282a4bc82]
  ponyc(ast_visit+0x1c5) [0x561282a4bc82]
  ponyc(ast_visit+0x1c5) [0x561282a4bc82]
  ponyc(ast_visit+0x1c5) [0x561282a4bc82]
  ponyc(ast_visit+0x1c5) [0x561282a4bc82]
  ponyc(ast_visit+0x1c5) [0x561282a4bc82]
  ponyc(+0x50341) [0x561282a4b341]
  ponyc(+0x506d4) [0x561282a4b6d4]
  ponyc(ast_passes_program+0x28) [0x561282a4b89c]
  ponyc(program_load+0xc1) [0x561282aa2648]
  ponyc(+0x4fc34) [0x561282a4ac34]
  ponyc(main+0x19c) [0x561282a4ae65]
  /usr/lib/libc.so.6(__libc_start_main+0xea) [0x7f3fbd83ff4a]
  ponyc(_start+0x2a) [0x561282a4aaaa]
Aborted (core dumped)

[Theodus]

I can reproduce with latest ponyc

[Theodus]

This is a problem with the compiler name suggestions (assertion at line 228):

ponyc/src/libponyc/pass/refer.c

Lines 192 to 233 in 0dfa0e6

	static const char* suggest_alt_name(ast_t* ast, const char* name)
	{
	pony_assert(ast != NULL);
	pony_assert(name != NULL);
	size_t name_len = strlen(name);
	if(is_name_private(name))
	{
	// Try without leading underscore
	const char* try_name = stringtab(name + 1);
	if(ast_get(ast, try_name, NULL) != NULL)
	return try_name;
	}
	else
	{
	// Try with a leading underscore
	char* buf = (char*)ponyint_pool_alloc_size(name_len + 2);
	buf[0] = '_';
	strncpy(buf + 1, name, name_len + 1);
	const char* try_name = stringtab_consume(buf, name_len + 2);
	if(ast_get(ast, try_name, NULL) != NULL)
	return try_name;
	}
	// Try with a different case (without crossing type/value boundary)
	ast_t* case_ast = ast_get_case(ast, name, NULL);
	if(case_ast != NULL)
	{
	ast_t* id = case_ast;
	if(ast_id(id) != TK_ID)
	id = ast_child(id);
	pony_assert(ast_id(id) == TK_ID);
	const char* try_name = ast_name(id);
	if(ast_get(ast, try_name, NULL) != NULL)
	return try_name;
	}

[winksaville]

PR #2552 is a possible fix for this issue.

[winksaville]

Fixed with #2552 being merged.