maintains internally, so you'll be desperately disappointed if
you try to glob etc. inside <literal>OPTIONS_GHC</literal>.</para>
- <para>NOTE: the contents of OPTIONS_GHC are prepended to the
- command-line options, so you <emphasis>do</emphasis> have the
- ability to override OPTIONS_GHC settings via the command
- line.</para>
+ <para>NOTE: the contents of OPTIONS_GHC are appended to the
+ command-line options, so options given in the source file
+ override those given on the command-line.</para>
<para>It is not recommended to move all the contents of your
Makefiles into your source files, but in some circumstances, the
<varlistentry>
<term>
<cmdsynopsis>
+ <command>ghc --supported-languages</command>
+ </cmdsynopsis>
+ <indexterm><primary><option>––supported-languages</option></primary></indexterm>
+ </term>
+ <listitem>
+ <para>Print the supported language extensions.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <cmdsynopsis>
+ <command>ghc --info</command>
+ </cmdsynopsis>
+ <indexterm><primary><option>––info</option></primary></indexterm>
+ </term>
+ <listitem>
+ <para>Print information about the compiler.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <cmdsynopsis>
<command>ghc --version</command>
<command>ghc -V</command>
</cmdsynopsis>
</listitem>
</varlistentry>
+ <varlistentry>
+ <term>
+ <cmdsynopsis>
+ <command>ghc --print-docdir</command>
+ </cmdsynopsis>
+ <indexterm><primary><option>––print-docdir</option></primary></indexterm>
+ </term>
+ <listitem>
+ <para>Print the path to GHC's documentation directory. Note that
+ some distributions do no include the documentation, in which case
+ this directory may be empty or may not exist.</para>
+ </listitem>
+ </varlistentry>
+
</variablelist>
<sect2 id="make-mode">
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><option>-Wwarn</option>:</term>
+ <listitem>
+ <indexterm><primary><option>-Wwarn</option></primary></indexterm>
+ <para>Warnings are treated only as warnings, not as errors. This is
+ the default, but can be useful to negate a
+ <option>-Werror</option> flag.</para>
+ </listitem>
+ </varlistentry>
+
</variablelist>
<para>The full set of warning options is described below. To turn