Re: c/6800: bad warnings for flexible arrays

Re: c/6800: bad warnings for flexible arrays

[rth]

Synopsis: bad warnings for flexible arrays

State-Changed-From-To: open->closed
State-Changed-By: rth
State-Changed-When: Tue May 28 09:56:18 2002
State-Changed-Why:
    It doesn't warn, it errors.  And what did you expect, anyway?
    When's the last time array assignment was defined in C?
    You get the same errors from a fixed size array.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=6800

c/6800: bad warnings for flexible arrays

[davem]

>Number:         6800
>Category:       c
>Synopsis:       bad warnings for flexible arrays
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri May 24 10:46:01 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     davem@redhat.com
>Release:        3.1
>Organization:
>Environment:
sparc-unknown-linux
>Description:
Operations, such as __typeof__(f->bar) warn
when the 'bar' member of 'f' is a flexible
array.

See attachment source, it warns:

? gcc -c -o flex.o flex.c
flex.c: In function `bar':
flex.c:8: array initialized from non-constant array expression
flex.c:8: storage size of `b' isn't known
>How-To-Repeat:
gcc -c -o flex.o flex.c
>Fix:
Shrug... don't use flexible arrays :-)
>Release-Note:
>Audit-Trail:
>Unformatted:
----gnatsweb-attachment----
Content-Type: application/octet-stream; name="flex.c"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="flex.c"

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