[project @ 2003-02-17 15:14:25 by simonpj]

More notes about building on Win32

docs/building/building.sgml

@@ -4366,13 +4366,22 @@ can be really confusing.
     <filename>fptools/</filename> thus:
 
 <Screen>
-  ./configure --host=i386-unknown-mingw32 --with-gcc=/mingw/bin/gcc
+  ./configure --host=i386-unknown-mingw32 --with-gcc=c:/mingw/bin/gcc
 </Screen>
 This is the point at which you specify that you are building GHC-mingw
-(see <xref linkend="ghc-mingw">).  
-
-Both these options are important! It's possible to get into
-trouble using the wrong C compiler!</para>
+(see <xref linkend="ghc-mingw">). </para>
+
+<para> Both these options are important! It's possible to get into
+trouble using the wrong C compiler!
+Furthermore, it's very important that you specify a 
+full mingw path for <command>gcc</command>, not a cygwin path, because GHC (which
+uses this path to invoke <command>gcc</command>) is a Mingw program and won't
+understand a cygwin path..  For example, if you 
+say <literal>--with-gcc=/mingw/bin/gcc</literal>, it'll be interpreted as
+<filename>/cygdrive/c/mingw/bin/gcc</filename>, and GHC will fail the first
+time it tries to invoke it.   (Worse, the failure does not come with
+a helpful error message, unfortunately.)
+</para>
 
 <para>
 If you want to build GHC-cygwin (<xref linkend="ghc-cygwin">)