Bug 652763 – Calling a generic async method of an abstract class on a non-generic subclass instance crashes valac

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Bug 652763 - Calling a generic async method of an abstract class on a non-generic subclass instance crashes valac


Summary:	Calling a generic async method of an abstract class on a non-generic subclass...


Status:	RESOLVED FIXED

Product:	vala
Classification:	Core
Component:	general
Version:	unspecified
Hardware:	Other All

Importance:	Normal critical
Target Milestone:	---
Assigned To:	Vala maintainers
QA Contact:	Vala maintainers

URL:
Whiteboard:

Depends on:
Blocks:	652643

Reported:	2011-06-16 17:28 UTC by Philip Withnall
Modified:	2011-06-17 10:59 UTC

See Also:
GNOME target:	---
GNOME version:	---

Description Philip Withnall 2011-06-16 17:28:00 UTC

The following test case is crashing valac for me:

public abstract class Abstract<T> : Object {
	public async List<T> my_method () {
		return new List<T> ();
	}
}

public class Subclass : Abstract<string> {
}

void main () {
	var foo = new Subclass ();
	foo.my_method.begin ((o, r) => {
		var result = foo.my_method.end (r);
	});
}

gives the following crash:

(gdb) run --pkg gio-2.0 test.vala
Starting program: /opt/gnome2/build/bin/valac --pkg gio-2.0 test.vala
[Thread debugging using libthread_db enabled]
**
ERROR:valasemanticanalyzer.c:3898:vala_semantic_analyzer_get_actual_type: assertion failed: (instance_type != NULL)

Program received signal SIGABRT, Aborted.
0x00110416 in __kernel_vsyscall ()
Missing separate debuginfos, use: debuginfo-install glibc-2.14-2.i686 libffi-3.0.9-2.fc15.i686
(gdb) t a a bt

+ Trace 227497

Thread 1 (Thread 0xb7fe36c0 (LWP 6182))

#0 __kernel_vsyscall
#1 raise
from /lib/libc.so.6
#2 abort
from /lib/libc.so.6
#3 g_assertion_message
#4 g_assertion_message_expr
at gtestutils.c line 1436
#5 vala_semantic_analyzer_get_actual_type
at valasemanticanalyzer.c line 3898
#6 vala_data_type_real_get_actual_type
at valadatatype.c line 1721
#7 vala_data_type_get_actual_type
at valadatatype.c line 1768
#8 vala_data_type_real_get_actual_type
at valadatatype.c line 1752
#9 vala_data_type_get_actual_type
at valadatatype.c line 1768
#10 vala_method_call_real_check
at valamethodcall.c line 3413
#11 vala_code_node_check
at valacodenode.c line 411
#12 vala_local_variable_real_check
at valalocalvariable.c line 771
#13 vala_code_node_check
at valacodenode.c line 411
#14 vala_declaration_statement_real_check
at valadeclarationstatement.c line 368
#15 vala_code_node_check
at valacodenode.c line 411
#16 vala_block_real_check
at valablock.c line 1847
#17 vala_code_node_check
at valacodenode.c line 411
#18 vala_method_real_check
at valamethod.c line 4034
#19 vala_code_node_check
at valacodenode.c line 411
#20 vala_lambda_expression_real_check
at valalambdaexpression.c line 2160
#21 vala_code_node_check
at valacodenode.c line 411
#22 vala_method_call_real_check
at valamethodcall.c line 3369
#23 vala_code_node_check
at valacodenode.c line 411
#24 vala_expression_statement_real_check
at valaexpressionstatement.c line 351
#25 vala_code_node_check
at valacodenode.c line 411
#26 vala_block_real_check
at valablock.c line 1847
#27 vala_code_node_check
at valacodenode.c line 411
#28 vala_method_real_check
at valamethod.c line 4034
#29 vala_code_node_check
at valacodenode.c line 411
#30 vala_source_file_check
at valasourcefile.c line 984
#31 vala_semantic_analyzer_real_visit_source_file
at valasemanticanalyzer.c line 2071
#32 vala_code_visitor_visit_source_file
at valacodevisitor.c line 1329
#33 vala_source_file_accept
at valasourcefile.c line 402
#34 vala_code_context_accept
at valacodecontext.c line 1119
#35 vala_semantic_analyzer_analyze
at valasemanticanalyzer.c line 2061
#36 vala_code_context_check
at valacodecontext.c line 1138
#37 vala_compiler_run
at valacompiler.c line 906
#38 vala_compiler_main
at valacompiler.c line 1605
#39 main
at valacompiler.c line 1614

Comment 1 Philip Withnall 2011-06-16 17:30:06 UTC

This is with git (master, ba518e654c4fad32dc4cecfb31b5dd19be3b2da4) from a few days ago.

Comment 2 Jürg Billeter 2011-06-17 10:59:29 UTC

commit e63a6456521bf4c6202339a68a1bfa09015da5a8
Author: Jürg Billeter <j@bitron.ch>
Date:   Fri Jun 17 12:48:32 2011 +0200

    Fix .begin and .end on async methods using generic types
    
    Fixes bug 652763.