c++/10648: template instantiation doesn't respect evaluation order of &&

c++/10648: template instantiation doesn't respect evaluation order of &&

[notbob]

>Number:         10648
>Category:       c++
>Synopsis:       template instantiation doesn't respect evaluation order of &&
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue May 06 22:56:01 UTC 2003
>Closed-Date:
>Last-Modified:
>Originator:     Robert Allan Schwartz
>Release:        gcc version 3.2 20020927 (prerelease)
>Organization:
>Environment:
in bash via cygwin on windows 98 se
>Description:
I apologize in advance if I'm not reporting this "bug"
absolutely correctly. I haven't done this before. I
appreciate your patience. Thank you.

I believe my template should evaluate is_class<T>::value first, and if it returns false, should NOT evaluate
sizeof(is_empty_helper_class_1<T>) ==
sizeof(is_empty_helper_class_2<T>), but it seems to anyway.

Is this "pilot error" or a compiler bug?
>How-To-Repeat:
g++ is_empty.cpp
./a.exe
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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Re: c++/10648: template instantiation doesn't respect evaluation order of &&

[giovannibajo]

Synopsis: template instantiation doesn't respect evaluation order of &&

State-Changed-From-To: open->closed
State-Changed-By: bajo
State-Changed-When: Wed May  7 00:34:17 2003
State-Changed-Why:
    Short-circuiting compilation of boolean expressions is not
    prescribed in the standard. Your code fails on any compiler
    I checked it in anyway, as a further confirm.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=10648