Document foreign import prim in the user guide

[ghc-hetmet.git] / docs / users_guide / bugs.xml

diff --git a/docs/users_guide/bugs.xml b/docs/users_guide/bugs.xml
index 50ffb39..7fd47c9 100644 (file)
--- a/docs/users_guide/bugs.xml
+++ b/docs/users_guide/bugs.xml
@@ -98,14 +98,28 @@ main = do args <- getArgs
 
       <para>GHC's typechecker makes all pattern bindings monomorphic
       by default; this behaviour can be disabled with
-      <option>-fno-mono-pat-binds</option>.  See <xref
+      <option>-XNoMonoPatBinds</option>.  See <xref
       linkend="options-language" />.</para>
     </sect3>
       
       <sect3 id="infelicities-Modules">
        <title>Module system and interface files</title>
        
-       <para>None known.</para>
+       <para>GHC requires the use of <literal>hs-boot</literal>
+         files to cut the recursive loops among mutually recursive modules
+         as described in <xref linkend="mutual-recursion"/>.  This more of an infelicity
+           than a bug: the Haskell Report says 
+         (<ulink url="http://haskell.org/onlinereport/modules.html#sect5.7">Section 5.7</ulink>) "Depending on the Haskell
+       implementation used, separate compilation of mutually
+       recursive modules may require that imported modules contain
+       additional information so that they may be referenced before
+       they are compiled. Explicit type signatures for all exported
+       values may be necessary to deal with mutual recursion. The
+       precise details of separate compilation are not defined by
+       this Report."
+
+       </para>
+
     </sect3>
 
     <sect3 id="infelicities-numbers">
@@ -284,6 +298,24 @@ checking for duplicates.  The reason for this is efficiency, pure and simple.
     </variablelist>
       
     </sect2>
+
+  <sect2 id="ffi-divergence">
+    <title>Divergence from the FFI specification</title>
+    
+    <variablelist>
+      <varlistentry>
+        <term><literal>hs_init()</literal> not allowed
+        after <literal>hs_exit()</literal></term>
+        <listitem>
+          <para>The FFI spec requires the implementation to support
+            re-initialising itself after being shut down
+            with <literal>hs_exit()</literal>, but GHC does not
+            currently support that.</para>
+        </listitem>
+      </varlistentry>
+    </variablelist>
+  </sect2>
+    
   </sect1>