Bug 1208760

It is due to the Fedora guile packaging not being multilib-clean:

WARNING: The command below may remove more packages due to dependencies!

yum -y remove guile.{x86_64,i686};yum -y install guile.x86_64;yum -y install guile.i686;yum -y remove guile.i686;rpm -V guile.x86_64;yum -y remove guile.x86_64
.......T.    /usr/bin/guild
.......T.    /usr/share/guile/2.0/guile-procedures.txt
.......T.    /usr/share/guile/2.0/ice-9/and-let-star.scm
.......T.    /usr/share/guile/2.0/ice-9/binary-ports.scm
[...]

Reproducible on F-21, F-22 and Rawhide.

It is unrelated to GDB, the same problem happens running just 'guile'.

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This is reproducible by simply installing first the x86_64 version and then the i686 version on an x86_64 system and then running guile.

Guile tries to compile everything because the timestamps of the source file and its corresponding guile object file (compiled go files) differ. New compiled objects are created in a cache directory inside the user's home, that's why the compilation executes everytime guile is run.

But, why does rpm modify the scm files if they are identical?

guile-2.0.11-7.fc23 has been submitted as an update to Fedora 23. https://bodhi.fedoraproject.org/updates/FEDORA-2015-44cdeeefb3

guile-2.0.11-7.fc22 has been submitted as an update to Fedora 22. https://bodhi.fedoraproject.org/updates/FEDORA-2015-7919a08cf4

guile-2.0.11-7.fc22 has been pushed to the Fedora 22 testing repository. If problems still persist, please make note of it in this bug report.
If you want to test the update, you can install it with
$ su -c 'dnf --enablerepo=updates-testing update guile'
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2015-7919a08cf4

guile-2.0.11-7.fc23 has been pushed to the Fedora 23 testing repository. If problems still persist, please make note of it in this bug report.
If you want to test the update, you can install it with
$ su -c 'dnf --enablerepo=updates-testing update guile'
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2015-44cdeeefb3

Rpm allows sharing files whose content is identical but timestamp differs, and yes it can cause artifacts like timestamp verification failures in some situations. With the exception of %config files, rpm does not compare contents when laying down files so the last one wins.

guile-2.0.11-7.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.

guile-2.0.11-7.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.