X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=docs%2Fusers_guide%2Fbugs.xml;h=4d79d24268e5e587434f157e41e8559d1ece1dd4;hb=aedb94f5f220b5e442b23ecc445fd38c8d9b6ba0;hp=fdeeaa87ccc277356bb0e68c0934e74c0e3baf4d;hpb=0f5e104c36b1dc3d8deeec5fef3d65e7b3a1b5ad;p=ghc-hetmet.git

diff --git a/docs/users_guide/bugs.xml b/docs/users_guide/bugs.xml
index fdeeaa8..4d79d24 100644
--- a/docs/users_guide/bugs.xml
+++ b/docs/users_guide/bugs.xml
@@ -105,7 +105,21 @@ main = do args <- getArgs
       <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">