Building with --disable-werror and -lto

Building with --disable-werror and -lto

[Damian Rouson]

All,

Could anyone provide feedback on the advisability of configuring with the lto language and —disable-werror flag when building gfortran?  I started using these years ago on the advice of a gfortran developer, but I’m wondering if the advice might have been specific to the state of development at the time or whether it’s still generally safest and/or leads to better optimization to use these flags.

In case anyone wants any further background, I typically build gfortran using the OpenCoarrays install.sh script, which uses the steps below when invoked with -z or —disable-bootstrap.  These steps still work for me with the GCC trunk, but “make install” fails with the teams branch of the Sourcery Institute GCC fork, which contains GCC commits through 28 November plus commits supporting Fortran 2018 teams.  At the advice of Cranfield Ph.D. student Soren Rasmussen, I resolved the problem by removing “,lto” and —desable-werror and now I’m trying to decide whether I should make this change the default for the OpenCoarrays install.sh script.


<path-to-gcc-source>/configure —prefix=<install-path> --enable-languages=c,c++,fortran,lto --disable-multilib --disable-werror —disable-bootstrap  
make
make install

Unfortunately, I no longer have the error message handy, but I know it happened at the “make install” step and it wasn’t related to permissions. 

Damian