[project @ 2001-10-16 11:29:08 by simonmar]

mention that you might need to add -lHSrts before any other libraries
on the linker command line, if another library has its own main() function.

diff --git a/ghc/docs/users_guide/phases.sgml b/ghc/docs/users_guide/phases.sgml
index 01ac535..3454483 100644 (file)
--- a/ghc/docs/users_guide/phases.sgml
+++ b/ghc/docs/users_guide/phases.sgml
@@ -299,6 +299,22 @@ strmod = "\
             come <emphasis>before</emphasis>
             <option>-l</option><replaceable>bar</replaceable> on the
             command line.</para>
+
+           <para>There's one other gotcha to bear in mind when using
+           external libraries: if the library contains a
+           <literal>main()</literal> function, then this will be
+           linked in preference to GHC's own
+           <literal>main()</literal> function
+           (eg. <literal>libf2c</literal> and <literal>libl</literal>
+           have their own <literal>main()</literal>s).  This is
+           because GHC's <literal>main()</literal> comes from the
+           <literal>HSrts</literal> library, which is normally
+           included <emphasis>after</emphasis> all the other
+           libraries on the linker's command line.  To force GHC's
+           <literal>main()</literal> to be used in preference to any
+           other <literal>main()</literal>s from external libraries,
+           just add the option <option>-lHSrts</option> before any
+           other libraries on the command line.</para>
          </listitem>
        </varlistentry>