mirror of
git://gcc.gnu.org/git/gcc.git
synced 2024-12-23 01:19:47 +08:00
c0ed1dea37
2000-07-11 Phil Edwards <pme@sourceware.cygnus.com> * docs: Update sourceware->sources in every HTML file. Minor updates. From-SVN: r34967
131 lines
5.2 KiB
HTML
131 lines
5.2 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN">
|
|
<HTML>
|
|
<HEAD>
|
|
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
|
|
<META NAME="AUTHOR" CONTENT="pme@sources.redhat.com (Phil Edwards)">
|
|
<META NAME="KEYWORDS" CONTENT="libgcc.a, rebuild">
|
|
<META NAME="DESCRIPTION" CONTENT="How to automatically rebuild libgcc.a.">
|
|
<META NAME="GENERATOR" CONTENT="vi and eight fingers">
|
|
<TITLE>How to automatically rebuild libgcc.a.</TITLE>
|
|
<LINK REL="home" HREF="http://sources.redhat.com/libstdc++/">
|
|
<LINK REL=StyleSheet HREF="lib3styles.css">
|
|
<!-- $Id: gccrebuild.html,v 1.4 2000/07/07 21:13:27 pme Exp $ -->
|
|
</HEAD>
|
|
<BODY>
|
|
|
|
<H2 CLASS="centered"><TT>--enable-libgcc-rebuild</TT></H2>
|
|
|
|
<P><B>NOTA BENE</B>: If using the <TT>--enable-libstdcxx-v3</TT> approach
|
|
to configuring, the std namespace will be turned on for you, without
|
|
going this route. Only use this flag if you'd like to experiment
|
|
with yet more binary incompatibilities, as discussed below.
|
|
</P>
|
|
|
|
<HR>
|
|
|
|
<P>If you build libstdc++ using certain flags (e.g., -fnew-abi), then
|
|
programs that use some of the new C++ language features (like namespace
|
|
std and RTTI) will only link if the compiler's libgcc is built using
|
|
the same flags. Other extralinguistic flags (like -fsquangle to change
|
|
the name mangling algorithm) will have the same effect.
|
|
</P>
|
|
|
|
<P>Passing --enable-libgcc-rebuild to libstdc++'s configure script
|
|
means that when you type 'make' next, after libstdc++ is built,
|
|
then libgcc will also be rebuilt. If you've given other
|
|
--enable/--with switches to libstdc++ that would require a core
|
|
library rebuild, then those compiler options will be automatically
|
|
used when compiling libgcc, such that both libraries will always be
|
|
built with the same options.
|
|
</P>
|
|
|
|
<P>The argument to this enable switch is the path to the GCC build
|
|
directory. The GCC configuration documentation refers to this directory
|
|
as <EM>objdir</EM>; here it will be called <EM>GCCobjdir</EM>.
|
|
</P>
|
|
|
|
<P>This was required for a few busy months of development, but was
|
|
always acknowledged a kludge. After the library sources were merged into
|
|
the compiler sources, this was commented out. If you must re-enable
|
|
it, you amy do so by uncommenting the GLIBCPP_ENABLE_RELIBGCC line in
|
|
configure.in and regenerating.
|
|
</P>
|
|
|
|
<HR>
|
|
|
|
<H3>If you kept your <EM>GCCobjdir</EM></H3>
|
|
<P>Easy as pi, er, pie. Just pass the pathname to the --enable switch
|
|
(absolute pathnames are best), and build libstdc++ as you normally
|
|
would. When it is finished, 'make' will go over to <EM>GCCobjdir</EM>
|
|
and build a new libgcc.a for you.
|
|
</P>
|
|
<P>Once that's done, skip down to "Installing the new libgcc.a."
|
|
</P>
|
|
|
|
|
|
<H3>If you deleted your <EM>GCCobjdir</EM>, or never had one</H3>
|
|
<P>Aaargggghhh, you had to make things difficult. Okay, note for future
|
|
reference: if you plan on experimenting with weird features, you'll want
|
|
to keep your build directories around. If you're having to re-unpack
|
|
the GCC source for this step, the same thing applies.
|
|
</P>
|
|
<P>We don't put a whole lot of effort into supporting this, so you might
|
|
just have to go the long way 'round if you run into difficulties.
|
|
</P>
|
|
<P>You'll have to trick the configure script into believing that libgcc.a
|
|
has been previously built. You'll also have to build the libraries that
|
|
libgcc.a needs. The steps are these:
|
|
<OL>
|
|
<LI>Unpack the GCC sources. Call this directory <EM>GCCsrcdir</EM>.
|
|
<LI>"<TT>mkdir <EM>GCCobjdir</EM> && cd <EM>GCCobjdir</EM> &&
|
|
<EM>GCCsrcdir</EM>/configure --whatever</TT>"
|
|
<BR>Configure GCC like you normally would. See
|
|
<A HREF="http://gcc.gnu.org/install/configure.html">the GCC
|
|
configuration instructions</A> for all the possible values
|
|
of <TT>--whatever</TT>.
|
|
<LI>"<TT>cd libiberty && make</TT>"
|
|
<LI>"<TT>cd ../gcc; touch libgcc2.ready</TT>"
|
|
</OL>
|
|
Now go back to "If you kept your GCCobjdir" and proceed from there.
|
|
</P>
|
|
|
|
|
|
<H3>Installing the new libgcc.a</H3>
|
|
<P>The reckless method is
|
|
<PRE>
|
|
cd GCCobjdir/gcc
|
|
make install-libgcc</PRE>
|
|
This will copy in the new libgcc.a on top of the old one.
|
|
</P>
|
|
<P>The wiser method is to keep the old one around under a different name,
|
|
and install the new one under another different name, and then make
|
|
libgcc.a be a hard or soft link to one of the two real libraries. Or
|
|
copy one of them by a new name into a directory searched by the linker,
|
|
and use -l (dash ell) to pick it up before finding the default
|
|
<EM>other</EM> library.
|
|
</P>
|
|
|
|
<HR>
|
|
|
|
<P>If you're <B>really</B> interested in using a particular flag (say,
|
|
-fhonor-std) under <B>all</B> conditions, then you can edit
|
|
<EM>GCCsrcdir</EM>/gcc/cp/decl2.c and change the initialization of the
|
|
appropriate <TT>flag_</TT> variable to 1. This will turn that flag
|
|
on by default, which means that libgcc.a, libstdc++.a, libstdc++.so,
|
|
and everything else you ever do will be built with that feature
|
|
unless you specifically turn it <EM>off</EM>.
|
|
</P>
|
|
|
|
|
|
<!-- ####################################################### -->
|
|
|
|
<HR>
|
|
<P CLASS="fineprint"><EM>
|
|
$Id: gccrebuild.html,v 1.4 2000/07/07 21:13:27 pme Exp $
|
|
</EM></P>
|
|
|
|
|
|
</BODY>
|
|
</HTML>
|
|
|