https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61954
--- Comment #3 from H.J. Lu <hjl.tools at gmail dot com> --- s-os_lib.adb has function Write (FD : File_Descriptor; A : System.Address; N : Integer) return Integer is begin return Integer (System.CRTL.write (System.CRTL.int (FD), System.CRTL.chars (A), System.CRTL.size_t (N))); end Write; It is compiled into jmp write 'A' should be a pointer, not integer.