Date: Mon, 18 Mar 1996 18:38:23 -0800 From: John Polstra <jdp@polstra.com> To: "Marty Leisner" <leisner@sdsp.mc.xerox.com> Cc: Michael Smith <msmith@atrad.adelaide.edu.au>, coredump@nervosa.com (invalid opcode), freebsd-current@freebsd.org Subject: Re: Elfkit release 1.1 is now available Message-ID: <199603190238.SAA04211@austin.polstra.com> In-Reply-To: Your message of "Mon, 18 Mar 1996 11:36:10 PST." <9603181936.AA25032@gnu.mc.xerox.com>
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Marty asked:
> With the ELF stuff:
> 1) should I be able to do reasonable cross-development from a linux paltform?
You mean, using the standard Linux compiler, right? (The tools in
elfkit are configured to run under FreeBSD, not under Linux.)
> 2) is there a difference between linux-elf and freebsd-elf?
> Or is it just i386-elf?
For the binutils stuff (assembler and linker): The configuration
target, i386-*-freebsdelf, is virtually identical to i386-*-elf.
There's really only one difference: The load address for executables is
set to 0x08048000, instead of the 0x08000000 that binutils uses for the
other ELF targets. Why? Because that's what the SVR4/i386 ABI
specification says it should be. (And that's what it really is, under
SVR4.) I don't know why 0x08000000 was used for Linux and friends.
Aside from that, I added a couple of command-line options, to make the
tools more compatible with the standard FreeBSD tools. For "as", the
"-k" option is accepted but ignored. The FreeBSD assembler uses "-k" to
specify that PIC code should be generated. For "ld", "-Bshareable" is
accepted as an alias for "-shared".
For gcc, the i386-*-freebsdelf differs from the Linux ELF target in
additional ways. Among the differences are:
* The predefines for cpp ("FreeBSD" instead of "linux")
* The type of wchar_t (int instead of long int)
* The LINK_SPEC
I hope this answers your questions. If not, let me know.
--
John Polstra jdp@polstra.com
John D. Polstra & Co., Inc. Seattle, Washington USA
"Self-knowledge is always bad news." -- John Barth
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