Re: problem with dynamic_cast

[Chris Faylor <cgf@cygnus.com>]

On Tue, Sep 12, 2000 at 02:55:00PM +0100, David Starks-Browning wrote:
>On Friday 8 Sep 00, Chris Faylor writes:
>> On Fri, Sep 08, 2000 at 12:46:31PM -0400, Chris Faylor wrote:
>> >On Fri, Sep 08, 2000 at 10:18:42AM -0400, Fleischer, Karsten (K.) wrote:
>> >>How about including the stub libraries in the distribution, rather than the
>> >>symlinks?
>> >
>> >The reason for the symlinks is that some packages search libc.a and libm.a
>> >for symbols.
>> >
>> >If linking libc.a twice causes problems, then it *is* a bug in either gcc or
>> >ld.
>> >
>> >Mumit had vowed once to fix this problem but then he disappeared...
>> 
>> Ok, I looked into this.  It is a linker problem.  Specifying -lm or -lc on
>> the command line causes ld to put symbols into the import section in improperly
>> sorted order.
>> 
>> This confuses the Windows "dynamic loader" (and I use the term loosely) so that
>> certain function calls (namely strcmp and strlen) are not resolved.  So when
>> a function in libgcc needs to call strcmp it ends up jumping into unallocated
>> memory, causing a SIGSEGV.
>> 
>> That's the analysis.  I have no idea how to fix this, but I've sent some details
>> to DJ in the hopes that he'll be able to do something about this.
>
>Would it be helpful if I put this in the FAQ?
>(Under "Known Problems in the Current Net Release".)

Yes.  "We" (this is the royal we) are working on the problem in the meantime.

cgf

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