has been specified, then the object filename is
<replaceable>dir</replaceable>/<replaceable>mod</replaceable>.<replaceable>osuf</replaceable>,
where <replaceable>mod</replaceable> is the module name with
- dots replaced by slashes. GHC will silently create the necessary directory
+ dots replaced by slashes. GHC will silently create the necessary directory
structure underneath <replaceable>dir</replaceable>, if it does not
- already exist.</para>
+ already exist.</para>
</listitem>
</itemizedlist>
<para>If you use <command>ghc --make</command> and you don't
use the <option>-o</option>, the name GHC will choose
for the executable will be based on the name of the file
- containing the module <literal>Main</literal>.
+ containing the module <literal>Main</literal>.
Note that with GHC the <literal>Main</literal> module doesn't
have to be put in file <filename>Main.hs</filename>.
Thus both
</varlistentry>
</variablelist>
</sect2>
-
+
<sect2 id="keeping-intermediates">
<title>Keeping Intermediate Files</title>
<indexterm><primary>intermediate files, saving</primary>
</indexterm>
<indexterm><primary><literal>.hc</literal> files, saving</primary>
</indexterm>
+ <indexterm><primary><literal>.ll</literal> files, saving</primary>
+ </indexterm>
<indexterm><primary><literal>.s</literal> files, saving</primary>
</indexterm>
<para>Keep intermediate <literal>.hc</literal> files when
doing <literal>.hs</literal>-to-<literal>.o</literal>
compilations via C (NOTE: <literal>.hc</literal> files
- aren't generated when using the native code generator, you
- may need to use <option>-fvia-C</option> to force them
- to be produced).</para>
+ are only generated by unregisterised compilers).</para>
</listitem>
</varlistentry>
<varlistentry>
<term>
- <option>-keep-s-file</option>,
- <option>-keep-s-files</option>
- <indexterm><primary><option>-keep-s-file</option></primary></indexterm>
- <indexterm><primary><option>-keep-s-files</option></primary></indexterm>
+ <option>-keep-llvm-file</option>,
+ <option>-keep-llvm-files</option>
+ <indexterm><primary><option>-keep-llvm-file</option></primary></indexterm>
+ <indexterm><primary><option>-keep-llvm-files</option></primary></indexterm>
</term>
<listitem>
- <para>Keep intermediate <literal>.s</literal> files.</para>
+ <para>Keep intermediate <literal>.ll</literal> files when
+ doing <literal>.hs</literal>-to-<literal>.o</literal>
+ compilations via LLVM (NOTE: <literal>.ll</literal> files
+ aren't generated when using the native code generator, you
+ may need to use <option>-fllvm</option> to force them
+ to be produced).</para>
</listitem>
</varlistentry>
<varlistentry>
<term>
- <option>-keep-raw-s-file</option>,
- <option>-keep-raw-s-files</option>
- <indexterm><primary><option>-keep-raw-s-file</option></primary></indexterm>
- <indexterm><primary><option>-keep-raw-s-files</option></primary></indexterm>
+ <option>-keep-s-file</option>,
+ <option>-keep-s-files</option>
+ <indexterm><primary><option>-keep-s-file</option></primary></indexterm>
+ <indexterm><primary><option>-keep-s-files</option></primary></indexterm>
</term>
<listitem>
- <para>Keep intermediate <literal>.raw-s</literal> files.
- These are the direct output from the C compiler, before
- GHC does “assembly mangling” to produce the
- <literal>.s</literal> file. Again, these are not produced
- when using the native code generator.</para>
+ <para>Keep intermediate <literal>.s</literal> files.</para>
</listitem>
</varlistentry>
This section explains how.</para>
<para>Every cycle in the module import graph must be broken by a <filename>hs-boot</filename> file.
- Suppose that modules <filename>A.hs</filename> and <filename>B.hs</filename> are Haskell source files,
+ Suppose that modules <filename>A.hs</filename> and <filename>B.hs</filename> are Haskell source files,
thus:
<programlisting>
module A where
import B( TB(..) )
-
+
newtype TA = MkTA Int
-
+
f :: TB -> TA
f (MkTB x) = MkTA x
module B where
import {-# SOURCE #-} A( TA(..) )
-
+
data TB = MkTB !Int
-
+
g :: TA -> TB
g (MkTA x) = MkTB x
</programlisting>
<programlisting>
ghc -c A.hs-boot
</programlisting>
-When a hs-boot file <filename>A.hs-boot</filename>
+When a hs-boot file <filename>A.hs-boot</filename>
is compiled, it is checked for scope and type errors.
When its parent module <filename>A.hs</filename> is compiled, the two are compared, and
an error is reported if the two are inconsistent.
</para></listitem>
-
+
<listitem>
<para> Just as compiling <filename>A.hs</filename> produces an
interface file <filename>A.hi</filename>, and an object file
<command>ghc -M</command> will report an error if a cycle is found.
</para></listitem>
- <listitem><para> A module <literal>M</literal> that is
+ <listitem><para> A module <literal>M</literal> that is
<literal>{-# SOURCE #-}</literal>-imported in a program will usually also be
ordinarily imported elsewhere. If not, <command>ghc --make</command>
automatically adds <literal>M</literal> to the set of modules it tries to
<para>A hs-boot file is written in a subset of Haskell:
<itemizedlist>
<listitem><para> The module header (including the export list), and import statements, are exactly as in
-Haskell, and so are the scoping rules.
+Haskell, and so are the scoping rules.
Hence, to mention a non-Prelude type or class, you must import it.</para></listitem>
-
+
<listitem><para> There must be no value declarations, but there can be type signatures for
values. For example:
<programlisting>
</para></listitem>
<listitem><para> Fixity declarations are exactly as in Haskell.</para></listitem>
<listitem><para> Type synonym declarations are exactly as in Haskell.</para></listitem>
-<listitem><para> A data type declaration can either be given in full, exactly as in Haskell, or it
+<listitem><para> A data type declaration can either be given in full, exactly as in Haskell, or it
can be given abstractly, by omitting the '=' sign and everything that follows. For example:
<programlisting>
data T a b
You <emphasis>can</emphasis> also write out the constructors but, if you do so, you must write
it out precisely as in its real definition.</para>
<para>
- If you do not write out the constructors, you may need to give a kind
+ If you do not write out the constructors, you may need to give a kind
annotation (<xref linkend="kinding"/>), to tell
GHC the kind of the type variable, if it is not "*". (In source files, this is worked out
from the way the type variable is used in the constructors.) For example:
brought up to date. To bring it up to date,
<literal>make</literal> looks for a rule to do so; one of the
preceding suffix rules does the job nicely. These dependencies
- can be generated automatically by <command>ghc</command>; see
+ can be generated automatically by <command>ghc</command>; see
<xref linkend="makefile-dependencies"/></para>
</sect2>
<filename>Makefile</filename>.</para>
<para>In general, <command>ghc -M Foo</command> does the following.
- For each module <literal>M</literal> in the set
+ For each module <literal>M</literal> in the set
<literal>Foo</literal> plus all its imports (transitively),
it adds to the Makefile:
<itemizedlist>
(See <xref linkend="mutual-recursion"/> for details of
<literal>hi-boot</literal> style interface files.)
</para></listitem>
- </itemizedlist>
+ </itemizedlist>
If <literal>M</literal> imports multiple modules, then there will
be multiple lines with <filename>M.o</filename> as the
target.</para>
<option>––include-pkg-deps</option> option below).</para>
<para>The dependency generation phase of GHC can take some
- additional options, which you may find useful. For historical
- reasons, each option passed to the dependency generator from
- the GHC command line must be preceded by
- <literal>-optdep</literal>. For example, to pass <literal>-f
- .depend</literal> to the dependency generator, you say
-
-<screen>
-ghc -M -optdep-f -optdep.depend ...
-</screen>
+ additional options, which you may find useful.
The options which affect dependency generation are:</para>
<term><option>-ddump-mod-cycles</option></term>
<listitem>
<para>Display a list of the cycles in the module graph. This is
- useful when trying to eliminate such cycles. You do not need the <literal>-optdep</literal> prefix
- for this flag.</para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>-w</option></term>
- <listitem>
- <para>Turn off warnings about interface file shadowing.</para>
+ useful when trying to eliminate such cycles.</para>
</listitem>
</varlistentry>
</varlistentry>
<varlistentry>
- <term><option>-f</option> <replaceable>file</replaceable></term>
+ <term><option>-dep-makefile</option> <replaceable>file</replaceable></term>
<listitem>
<para>Use <replaceable>file</replaceable> as the makefile,
rather than <filename>makefile</filename> or
<filename>Makefile</filename>. If
<replaceable>file</replaceable> doesn't exist,
<command>mkdependHS</command> creates it. We often use
- <option>-f .depend</option> to put the dependencies in
+ <option>-dep-makefile .depend</option> to put the dependencies in
<filename>.depend</filename> and then
<command>include</command> the file
<filename>.depend</filename> into
</listitem>
</varlistentry>
-<!-- Retired with the move away from 'mkdependHS'.
<varlistentry>
- <term><option>-o <osuf></option></term>
- <listitem>
- <para>Use <filename>.<osuf></filename> as the
- "target file" suffix ( default: <literal>o</literal>).
- Multiple <option>-o</option> flags are permitted
- (GHC2.05 onwards). Thus "<option>-o hc -o o</option>"
- will generate dependencies for <filename>.hc</filename>
- and <filename>.o</filename> files.</para>
- </listitem>
- </varlistentry>
--->
- <varlistentry>
- <term><option>-s <suf></option></term>
+ <term><option>-dep-suffix <suf></option></term>
<listitem>
<para>Make extra dependencies that declare that files
with suffix
<filename>.<suf>_hi</filename>, or (for
<literal>{-# SOURCE #-}</literal>
imports) on <filename>.hi-boot</filename>. Multiple
- <option>-s</option> flags are permitted. For example,
- <option>-o hc -s a -s b</option> will make dependencies
- for <filename>.hc</filename> on
+ <option>-dep-suffix</option> flags are permitted. For example,
+ <option>-dep-suffix a -dep-suffix b</option>
+ will make dependencies
+ for <filename>.hs</filename> on
<filename>.hi</filename>,
- <filename>.a_hc</filename> on
+ <filename>.a_hs</filename> on
<filename>.a_hi</filename>, and
- <filename>.b_hc</filename> on
+ <filename>.b_hs</filename> on
<filename>.b_hi</filename>. (Useful in
conjunction with NoFib "ways".)</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><option>-x</option></term>
- <listitem>
- <para>same as <option>––exclude-module</option></para>
- </listitem>
- </varlistentry>
-
-<!-- Not currently implemented:
- <varlistentry>
- <term><option>––exclude-directory=<dirs></option></term>
- <listitem>
- <para>Regard the colon-separated list of directories
- <filename><dirs></filename> as containing stable,
- don't generate any dependencies on modules
- therein.</para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>––include-module=<file></option></term>
- <listitem>
- <para>Regard <filename><file></filename> as not
- "stable"; i.e., generate dependencies on it (if
- any). This option is normally used in conjunction with
- the <option>––exclude-directory</option> option.</para>
- </listitem>
- </varlistentry>
--->
-
- <varlistentry>
<term><option>––include-pkg-deps</option></term>
<listitem>
<para>Regard modules imported from packages as unstable,
be a disaster in practice, so GHC tries to be clever. </para>
<para>In particular, if an instance declaration is in the same module as the definition
-of any type or class mentioned in the <emphasis>head</emphasis> of the instance declaration
+of any type or class mentioned in the <emphasis>head</emphasis> of the instance declaration
(the part after the “<literal>=></literal>”; see <xref linkend="instance-rules"/>), then
GHC has to visit that interface file anyway. Example:</para>
<programlisting>
least one <emphasis>orphan rule</emphasis>.</para> </listitem>
<listitem><para> An instance declaration in a module M is an <emphasis>orphan instance</emphasis> if
- <indexterm><primary>orphan instance</primary></indexterm>
-<itemizedlist>
+ <indexterm><primary>orphan instance</primary></indexterm>
+<itemizedlist>
<listitem><para>
The class of the instance declaration is not declared in M, and
</para></listitem>
</para></listitem>
</itemizedlist>
</para>
- <para> Only the instance head
+ <para> Only the instance head
counts. In the example above, it is not good enough for C's declaration
to be in module A; it must be the declaration of D or T.</para>
</listitem>
-<para>If you use the flag <option>-fwarn-orphans</option>, GHC will warn you
+<para>If you use the flag <option>-fwarn-orphans</option>, GHC will warn you
if you are creating an orphan module.
-Like any warning, you can switch the warning off with <option>-fno-warn-orphans</option>,
+Like any warning, you can switch the warning off with <option>-fno-warn-orphans</option>,
and <option>-Werror</option>
will make the compilation fail if the warning is issued.
</para>
<!-- Emacs stuff:
;;; Local Variables: ***
- ;;; mode: xml ***
;;; sgml-parent-document: ("users_guide.xml" "book" "chapter" "sect1") ***
;;; End: ***
-->
projects / ghc-hetmet.git / blobdiff