$ gdb main core.21010
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Reading symbols from /home/akira/tmp/src/shapefile.03/test.01/sample/io.shapefile/main...done.
[New Thread 21010]
Reading symbols from /usr/lib64/libgfortran.so.1...(no debugging symbols found)...done.
Loaded symbols for /usr/lib64/libgfortran.so.1
Reading symbols from /lib64/libm.so.6...(no debugging symbols found)...done.
Loaded symbols for /lib64/libm.so.6
Reading symbols from /lib64/libgcc_s.so.1...(no debugging symbols found)...done.
Loaded symbols for /lib64/libgcc_s.so.1
Reading symbols from /lib64/libc.so.6...(no debugging symbols found)...done.
Loaded symbols for /lib64/libc.so.6
Reading symbols from /lib64/ld-linux-x86-64.so.2...(no debugging symbols found)...done.
Loaded symbols for /lib64/ld-linux-x86-64.so.2

warning: no loadable sections found in added symbol-file system-supplied DSO at 0x7fff40f0b000
Core was generated by `./main'.
Program terminated with signal 11, Segmentation fault.
#0  0x0000003f02e719fd in _int_malloc () from /lib64/libc.so.6
(gdb) bt
#0  0x0000003f02e719fd in _int_malloc () from /lib64/libc.so.6
#1  0x0000003f02e73dfe in malloc () from /lib64/libc.so.6
#2  0x00002b31b91514e9 in ?? () from /usr/lib64/libgfortran.so.1
#3  0x00002b31b91bc329 in _gfortran_string_trim () from /usr/lib64/libgfortran.so.1
#4  0x0000000000402375 in shpgetrecords (shp=...) at mod_io_shapefile.f90:774
#5  0x00000000004015e0 in MAIN__ () at main.f90:16
#6  0x000000000041462e in main ()