libstdc++5 and gcc 3.3

Matthew Garrett mjg59 at
Mon Oct 9 23:33:36 BST 2006

On Mon, Oct 09, 2006 at 03:43:24PM -0400, John Richard Moser wrote:

> Can the ABI on this be rolled together into one library?  I recall doing
> things like finding apps demanding libstdc++5 and symlinking 6 to the
> .so they were looking for, which worked fine; to what extent it works
> fine I don't know, eventually some app will go "I CAN'T FIND A SYMBOL I
> WANT!!"

Not in any realistic way, no. The symbol mangling depends on the 
compiler used to build the library.

>  - Keep libstdc++5.  Safest, easiest option; but the library is 730K

I'm sure people will live.

>  - Symlink or hardlink libstdc++6 to libstdc++5.  May work, may not,
>    some apps will work with it but it is unknown (but likely) if any
>    will outright fail.

Will entirely fail to work, since they're from different C++ ABIs.

>  - Roll any libstdc++5 compatibility necessary and proper into
>    libstdc++6.  Any action breaking v6 programs will be impossible; but
>    ELF versioning allows this to be done feasibly.  Then
>    symlink/hardlink.  Probably safe, probably a lot of work.

Approximately impossible.

>  - Produce a thin wrapper library that adds proper compatibility
>    layers, and links to libstdc++6.  This is probably the safest and
>    easiest option that avoids installing libstdc++5.

Unbelievable pain.

The only sensible option is keeping libstdc++. 730K isn't worth weeks of 
developer time.

Matthew Garrett | mjg59 at

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