Vis: /builddir/build/BUILD/frysk-0.2.1/build/../frysk-core/frysk/pkglibdir/funit-watchpoint.S: Assembler messages: /builddir/build/BUILD/frysk-0.2.1/build/../frysk-core/frysk/pkglibdir/funit-watchpoint.S:55: Error: unsupported relocation against source Several things: // Load source variables address into GPR 1 LOAD_IMMED_BYTE (REG1, source) since it's loading the word-sized address (source) it should use LOAD_IMMED_WORD. // Write 0x77 into the location of source (held by GPR1) STORE(REG3, REG1) the store is word-sized, but source is only a byte in size.