pcp_reference_guide_v2.5 - Tasking

Linker Script Language8−51Copy table• The keyword copytable tells the linker to select a section that is usedas copy table. The content of the copy table is created by the linker. Itcontains the start address and length of all sections that should beinitialized by the startup code.The linker creates two labels to mark the begin and end of the section,_lc_ub_table for the start, and _lc_ue_table for the end of thecopy table. The linker generates a copy table when a reference toeither of the section labels exists in one of the input object files.8.8.4 CREATING SYMBOLSYou can tell the linker to create symbols before locating by puttingassignments in the section layout definition. Symbol names arerepresented by double−quoted strings. Any string is allowed, but objectfiles may not support all characters for symbol names. You can use twodifferent assignment operators. With the simple assignment operator ’=’,the symbol is created unconditionally. With the ’:=’ operator, the symbol isonly created if it already exists as an undefined reference in an object file.The expression that represents the value to assign to the symbol maycontain references to other symbols. If such a referred symbol is a specialsection symbol, creation of the symbol in the left hand side of theassignment will cause creation of the special section.section_layout{"_lc_bs" := "_lc_ub_stack";// when the symbol _lc_bs occurs as an undefined// reference in an object file,// the linker allocates space for the stack}• • • • • • • •