340aa4f687
Clang generates a warning if there is a function declaration/definition
with zero arguments. Such declarations/definitions without a prototype (an
argument list) are deprecated forms of indefinite arguments
("-Wdeprecated-non-prototype"). On the default configuration, it causes a
build failure (unless "--disable-werror" is specified).
include/getopt.h defines some getopt function definitions but one of them
has a form "extern int getopt ();". If this form is selected in
include/getopt.h, Clang generates a warning and the build fails by default.
In really old environments, this getopt definition with no arguments is
necessary (because the definition may change between environments).
However, this definition is now a cause of problems on modern environments.
A good news is, this definition is not always selected (e.g. if used by
binutils/*.c). This is because configuration scripts of binutils, gas,
gprof and ld tries to find known definition of getopt function is used and
defines HAVE_DECL_GETOPT macro. If this macro is defined when getopt.h is
included, a good form of getopt is used and Clang won't generate warnings.
This commit adds a modified portion of ld/configure.ac to find the known
getopt definition. If we could find one (and we *will* in most modern
environments), we don't need to rely on the deprecated definition.
README for GNU development tools This directory contains various GNU compilers, assemblers, linkers, debuggers, etc., plus their support routines, definitions, and documentation. If you are receiving this as part of a GDB release, see the file gdb/README. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.