ABI=32 on 64-bit system missing -D__USE_FILE_OFFSET64 (?)

[markuspf]

Configuring and compiling GAP as follows on a 64 bit system

# ./configure --with-gmp=system ABI=32
# gmake

yields a runnable executable, but sometimes GAP does not start complaining that it cannot find GAPDoc (even though this is installed, because the directory has a 64 bit ino for instance).

I traced this down to a call to stat in src/sysfiles.c:3756, it errors with errno set to 75 (value too large for datatype). This can be addressed by compiling GAP with -D__USE_FILE_OFFSET64 where available.

In a PR I will fix the functions FuncIsDirectoryPath and SyIsDirectoryPath to properly deal with failures and errno, to return fail instead of false.

[olexandr-konovalov]

@markuspf thanks for digging this out. Do you know why it did not happen on Jenkins slaves which we have used before?

[markuspf]

I'd have to look more in detail, but it'll have something to do with the filesystem having 64bit inode numbers, or something to a similar effect.

[markuspf]

Do @fingolfin or @ChrisJefferson have any opinion (or better knowledge) on this?

[olexandr-konovalov]

We have a new Jenkins slave in St Andrews which has this problem and throws test failure notifications every evening in the worst possible way: GAP can not be loaded in this configuration at all because GAPDoc package can not be loaded:

#I  gapdoc package is not available. Check that the name is correct
#I  and it is present in one of the GAP root directories (see '??RootPaths')
#I  GAP: needed package gapdoc cannot be loaded

[fingolfin]

I think the correct way to do this is to #define _FILE_OFFSET_BITS=64, but only if the system really sypports 64bit inodes (at least the glibc documentation demands this).
Autoconf has a macro for this, which we hopefully can use: AC_SYS_LARGEFILE

While I could add it (it needs to be added to cnf/configure.in), I cannot reliably test it. So perhaps somebody who has a test setup can verify it works? Otherwise, I'll create a PR and "test by proxy" (i.e. check that all the right #defines are set).

Oh, and this of course should then also go into the new build syste,.

[markuspf]

I have a system here that I can test this on. I think I can give you access to it if you're willing to tunnel your ssh through one of {yin,babbage,lovelace}, I'd need a ssh pubkey from you for that.

[fingolfin]

Can this be closed, now that #1033 has been merged?

[olexandr-konovalov]

Great - Jenkins tests now do not trip over this problem. Thanks!

[olexandr-konovalov]

@markuspf shall we fix this in stable-4.8 branch too? I am testing GAP 4.8.7 release candidate, and its shows up there on the same Jenkins slave. Alternatively, I can just disable testing 32-bit builds on that slave until GAP 4.9 will be out - perhaps nobody builds GAP in 32-bit mode on relatively modern 64-bit machines, otherwise we would hear about such problems already.

[olexandr-konovalov]

Ok, cherry picking works - should be fixed in GAP 4.8.7 then.