/usr/share/fpcsrc/2.6.2/packages/gmp/ is in fpc-source-2.6.2 2.6.2-8.
This file is owned by root:root, with mode 0o755.
..
/usr/share/fpcsrc/2.6.2/packages/gmp/Makefile.fpc
/usr/share/fpcsrc/2.6.2/packages/gmp/Package.fpc
/usr/share/fpcsrc/2.6.2/packages/gmp/examples/
/usr/share/fpcsrc/2.6.2/packages/gmp/examples/Makefile.fpc
/usr/share/fpcsrc/2.6.2/packages/gmp/examples/gmp_accept_test.pas
/usr/share/fpcsrc/2.6.2/packages/gmp/examples/gmp_test_impl.inc
/usr/share/fpcsrc/2.6.2/packages/gmp/examples/gmp_test_intf.inc
/usr/share/fpcsrc/2.6.2/packages/gmp/examples/gmp_testcase.pas
/usr/share/fpcsrc/2.6.2/packages/gmp/examples/pidigits_example.pas
/usr/share/fpcsrc/2.6.2/packages/gmp/examples/pidigits_example2.pas
/usr/share/fpcsrc/2.6.2/packages/gmp/examples/printf_example.pas
/usr/share/fpcsrc/2.6.2/packages/gmp/examples/printf_example2.pas
/usr/share/fpcsrc/2.6.2/packages/gmp/examples/scanf_example.pas
/usr/share/fpcsrc/2.6.2/packages/gmp/examples/scanf_example2.pas
/usr/share/fpcsrc/2.6.2/packages/gmp/fpmake.pp
/usr/share/fpcsrc/2.6.2/packages/gmp/src/
/usr/share/fpcsrc/2.6.2/packages/gmp/src/gmp.pas