A ? as input should dump the variable names of the namelist to standard output.
Like PR 18874, but with libfortran. $ cat namelist.f90 program main namelist /foo/ a read (*,foo) end $ gfortran namelist.f90 && ./a.out ? At line 3 of file namelist.f90 Fortran runtime error: Invalid character in namelist $ gfortran -v Reading specs from /home/ig25/lib/gcc/i686-pc-linux-gnu/4.0.0/specs Configured with: ../gcc/configure --prefix=/home/ig25 --enable-languages=c,c++,f95 --disable-shared : (reconfigured) ../gcc/configure --prefix=/home/ig25 --disable-shared --with-gcc-version-trigger=/home/ig25/gcc/gcc/version.c --enable-languages=c,c++,f95 --no-create --no-recursion Thread model: posix gcc version 4.0.0 20041206 (experimental) -- Summary: ? not supported in namelist input Product: gcc Version: 4.0.0 Status: UNCONFIRMED Severity: normal Priority: P2 Component: libfortran AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: Thomas dot Koenig at online dot de CC: gcc-bugs at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18879