Re: c++/10223: template trickery causes ICE (segmentation fault)

Re: c++/10223: template trickery causes ICE (segmentation fault)

[Volker Reichelt]

The following reply was made to PR c++/10223; it has been noted by GNATS.

From: Volker Reichelt <reichelt@igpm.rwth-aachen.de>
To: gcc-gnats@gcc.gnu.org, hg211@ural2.hszk.bme.hu, gcc-bugs@gcc.gnu.org,
 bangerth@ices.utexas.edu
Cc:  
Subject: Re: c++/10223: template trickery causes ICE (segmentation fault)
Date: Thu, 27 Mar 2003 22:36:29 +0100 (CET)

 Hi Wolfgang,
 
 this looks similar to PR 9634 to me.
 
 http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=9634
 
 Regards,
 Volker
 
 http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=10223
 
 

Re: c++/10223: template trickery causes ICE (segmentation fault)

[Giovanni Bajo]

The following reply was made to PR c++/10223; it has been noted by GNATS.

From: "Giovanni Bajo" <giovannibajo@libero.it>
To: <gcc-gnats@gcc.gnu.org>,
	<hg211@ural2.hszk.bme.hu>,
	<gcc-bugs@gcc.gnu.org>,
	<nobody@gcc.gnu.org>,
	<gcc-prs@gcc.gnu.org>
Cc:  
Subject: Re: c++/10223: template trickery causes ICE (segmentation fault)
Date: Fri, 2 May 2003 19:28:29 +0200

 http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=10223
 
 Not really related to c++/9364 (as shown by my recent analysys of that PR).
 Instead, an epurated code snippet of this PR looks this way:
 --------------------------------------------
 template <typename T>
 struct Foo
 {
     template <void (T::*)()>
     struct dummy;
 
     template <typename Q>
     static char test(dummy<&Q::whatever> *);
 };
 
 
 struct Bar {};
 
 template struct Foo<Bar>;
 //template struct Foo<int>;
 --------------------------------------------
 pr10223.cpp: In instantiation of `Foo<Bar>':
 pr10223.cpp:14:   instantiated from here
 pr10223.cpp:8: internal compiler error: Segmentation fault
 Please submit a full bug report,
 
 If you instantiate the template with a basic type instead of Bar (using the
 commented line instead of the other one), we get an ICE on error recovery:
 
 pr10223.cpp: In instantiation of `Foo<int>':
 pr10223.cpp:15:   instantiated from here
 pr10223.cpp:5: error: creating pointer to member function of non-class type
 `int'
 pr10223.cpp:5: internal compiler error: in retrieve_specialization, at
 cp/pt.c:894
 Please submit a full bug report,
 
 I keep both the ICEs in this same PR since they are very likely related.
 Reconfirmed on every GCC version I have (2.95 -> mainline CVS 20030430).
 
 After this redux has been fixed, I suggest trying again the original code
 provided by the poster, which could reveal other problems.
 
 Giovanni Bajo
 

Re: c++/10223: template trickery causes ICE (segmentation fault)

[bangerth]

Synopsis: template trickery causes ICE (segmentation fault)

State-Changed-From-To: open->analyzed
State-Changed-By: bangerth
State-Changed-When: Wed Mar 26 15:19:11 2003
State-Changed-Why:
    Confirmed with all versions including present mainline. I'm
    pretty sure this is a duplicate of some other report which
    I can't find at present, though.
    
    W.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=10223

c++/10223: template trickery causes ICE (segmentation fault)

[hg211]

>Number:         10223
>Category:       c++
>Synopsis:       template trickery causes ICE (segmentation fault)
>Confidential:   no
>Severity:       serious
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          ice-on-legal-code
>Submitter-Id:   net
>Arrival-Date:   Wed Mar 26 14:26:01 UTC 2003
>Closed-Date:
>Last-Modified:
>Originator:     Geza Herman
>Release:        All gcc versions
>Organization:
>Environment:
Linux 2.4.18 i686 Debian GNU/Linux
>Description:
The code sample causes ICE an all gcc versions I tried:
gcc version 2.95.4 20011002 (Debian prerelease)
gcc version 3.0.4
gcc version 3.2.3 20030316 (Debian prerelease)
gcc version 3.3 20030314 (prerelease)

The sample tries to get some meta-information: tries to determine if a class has a particular member-function.
('void save()' in this example)
>How-To-Repeat:
compile this sample:

template <typename T>
class hasSaveFunction {
	private:
		struct Helper {
			struct False { char dummy[1979]; };

			template <void (T::*)()>
			struct dummy;

			template <typename T2>
			static char test(dummy<&T2::save> *);

			template <typename T2>
			static False test(...);
		};

	public:
		static const bool value = sizeof(Helper::template test<T>(0))==1
;
};

class Dummy { };

int main() {
	return hasSaveFunction<Dummy>::value;
}
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted: