When using gfortran 4.3.1 with Fortran modules compiled by older, incompatible releases like 4.2.4, the error message emitted is vague and does not attempt to point out the possible incompatibility between compiler and Fortran module. Many users keep Fortran modules around and would encounter this error on upgrading to the newest gfortran release, but would have to hunt for an answer.
"Fatal Error: Reading module test at line 14 column 17: Expected string" > gcc -v -save-temps Using built-in specs. Target: x86_64-suse-linux Configured with: ../xt-gcc-4.3.1/configure --prefix=/opt/gcc/4.3.1/snos --disable-nls --libdir=/opt/gcc/4.3.1/snos/lib --enable-languages=c,c++,fortran --with-gxx-include-dir=/opt/gcc/4.3.1/snos/include/g++ --with-slibdir=/opt/gcc/4.3.1/snos/lib --with-system-zlib --enable-shared --enable-__cxa_atexit x86_64-suse-linux --with-mpfr=/opt/gcc/4.3.1/mpfr/2.3.1 Thread model: posix gcc version 4.3.1 20080606 (rpm:5) (GCC) -- Summary: better error needed for incompatible f90 modules Product: gcc Version: 4.3.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: fortran AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: colinlee at cray dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38993