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Re: Guile test-ffi uses an unportable assumption
From: |
Mark H Weaver |
Subject: |
Re: Guile test-ffi uses an unportable assumption |
Date: |
Wed, 10 Aug 2016 04:31:15 -0400 |
User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/25.1 (gnu/linux) |
Eli Zaretskii <address@hidden> writes:
>> From: Andy Wingo <address@hidden>
>> Cc: address@hidden
>> DATE: sat, 23 Jul 2016 23:17:58 +0200
>>
>> > It assumes that libltdl can only produce a handle for a symbol in the
>> > the program itself, as opposed to those loaded from shared libraries.
>> > It tries 'strerror'. This cannot work on MS-Windows, unless the
>> > program was linked with -export-dynamic, which is not true for
>> > the test program.
>>
>> Interesting. The test program is a Scheme script which looks up
>> strerror in the dlopen(NULL). Libguile is compiled with -export-dynamic
>> but the guile binary is not. Which part needs to be compiled with
>> -export-dynamic, do you think?
>
> The guile binary. Here's what the libltdl documentation has to say
> about this:
>
> -- Function: lt_dlhandle lt_dlopen (const char *FILENAME)
> [...]
> If FILENAME is `NULL' and the program was linked with
> `-export-dynamic' or `-dlopen self', `lt_dlopen' will return a
> handle for the program itself, which can be used to access its
> symbols.
> [...]
> If you use `lt_dlopen (NULL)' to get a HANDLE for the running
> binary, that handle will always be marked as resident, and
> consequently cannot be successfully `lt_dlclose'd.
>
> However, in the case in point even compiling guile with -export-dynamic
> won't help, because the function being used by the test, strerror,
> comes from the C library, and is not statically linked into the guile
> binary. So I suggest to modify the test to use a function that is
> part of the guile binary's own sources.
Sounds good to me. Here's a proposed patch. Can you test it on MinGW
and report back?
Thanks,
Mark
0001-test-ffi-In-global-symbol-test-use-functions-from-li.patch
Description: [PATCH] test-ffi: In global symbol test, use functions from libguile only.
- Re: Guile test-ffi uses an unportable assumption,
Mark H Weaver <=