Andrew Burgess 0a61824343 ld: Add '--require-defined' command line option. ... Add a new command line option '--require-defined' to the linker. This option operates identically to the '--undefined' option, except that if the symbol is not defined in the final output file then the linker will exit with an error. When making use of --gc-section, or just when trying to pull in parts of a library, it is not uncommon for a user to use the '--undefined' command line option to specify a symbol that the user then expects to be defined by one of the object files supplied to the link. However, if for any reason the symbol is not satisfied by an object provided to the link the user will be left with an undefined symbol in the output file, instead of a defined symbol. In some cases the above behaviour is what the user wants, in other cases though we can do better. The '--require-defined' option tries to fill this gap. The symbol passed to the '--require-defined' option is treated exactly as if the symbol was passed to '--undefined', however, before the linker exits a check is made that all symbols passed to '--require-defined' are actually defined, if any are not then the link will fail with an error. ld/ChangeLog: * ld.texinfo (Options): Document --require-defined option. * ldlang.c (struct require_defined_symbol): New structure. (require_defined_symbol_list): New variable. (ldlang_add_require_defined): New function. (ldlang_check_require_defined_symbols): New function. (lang_process): Check required symbols are defined. * ldlang.h (ldlang_add_require_defined): Declare. * ldlex.h (enum option_values): Add OPTION_REQUIRE_DEFINED_SYMBOL. * lexsup.c (ld_options): Add '--require-defined' entry. (parse_args): Handle '--require-defined' entry. * NEWS: Mention new '--require-defined' option. ld/testsuite/ChangeLog: * ld-undefined/require-defined-1.d: New file. * ld-undefined/require-defined-2.d: New file. * ld-undefined/require-defined-3.d: New file. * ld-undefined/require-defined-4.d: New file. * ld-undefined/require-defined-5.d: New file. * ld-undefined/require-defined.exp: New file. * ld-undefined/require-defined.s: New file.		2015-08-04 10:00:05 +01:00
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dummy.s
entry-1.d
entry-2.d
entry-3.d
entry-4.d
entry-5.d
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entry-7.d
entry.exp
entry.s
require-defined-1.d
require-defined-2.d
require-defined-3.d
require-defined-4.d
require-defined-5.d
require-defined.exp
require-defined.s
undefined.c
undefined.exp
weak-undef.exp
weak-undef.s
weak-undef.t