+ <para>Print single alternative case expressions as though they were strict
+ let expressions. This is helpful when your code does a lot of unboxing.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>-dno-debug-output</option>
+ <indexterm><primary><option>-dno-debug-output</option></primary></indexterm>
+ </term>
+ <listitem>
+ <para>Suppress any unsolicited debugging output. When GHC
+ has been built with the <literal>DEBUG</literal> option it
+ occasionally emits debug output of interest to developers.
+ The extra output can confuse the testing framework and
+ cause bogus test failures, so this flag is provided to
+ turn it off.</para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+
+ </sect2>
+
+ <sect2 id="supression">
+ <title>Suppressing unwanted information</title>
+
+ <indexterm><primary>suppression</primary></indexterm>
+
+ Core dumps contain a large amount of information. Depending on what you are doing, not all of it will be useful.
+ Use these flags to suppress the parts that you are not interested in.
+
+ <variablelist>
+ <varlistentry>
+ <term>
+ <option>-dsuppress-all</option>
+ <indexterm><primary><option>-dsuppress-all</option></primary></indexterm>
+ </term>
+ <listitem>
+ <para>Suppress everything that can be suppressed, except for unique ids as this often
+ makes the printout ambiguous. If you just want to see the overall structure of
+ the code, then start here.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>-dsuppress-uniques</option>
+ <indexterm><primary><option>-dsuppress-uniques</option></primary></indexterm>
+ </term>
+ <listitem>
+ <para>Suppress the printing of uniques. This may make
+ the printout ambiguous (e.g. unclear where an occurrence of 'x' is bound), but
+ it makes the output of two compiler runs have many fewer gratuitous differences,
+ so you can realistically apply <command>diff</command>. Once <command>diff</command>
+ has shown you where to look, you can try again without <option>-dsuppress-uniques</option></para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>-dsuppress-idinfo</option>
+ <indexterm><primary><option>-dsuppress-idinfo</option></primary></indexterm>
+ </term>
+ <listitem>
+ <para>Suppress extended information about identifiers where they are bound. This includes
+ strictness information and inliner templates. Using this flag can cut the size
+ of the core dump in half, due to the lack of inliner templates</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>-dsuppress-module-prefixes</option>
+ <indexterm><primary><option>-dsuppress-module-prefixes</option></primary></indexterm>
+ </term>
+ <listitem>
+ <para>Suppress the printing of module qualification prefixes.
+ This is the <constant>Data.List</constant> in <constant>Data.List.length</constant>.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>-dsuppress-type-signatures</option>
+ <indexterm><primary><option>-dsuppress-type-signatures</option></primary></indexterm>
+ </term>
+ <listitem>
+ <para>Suppress the printing of type signatures.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>-dsuppress-type-applications</option>
+ <indexterm><primary><option>-dsuppress-type-applications</option></primary></indexterm>
+ </term>
+ <listitem>
+ <para>Suppress the printing of type applications.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>-dsuppress-coercions</option>
+ <indexterm><primary><option>-dsuppress-coercions</option></primary></indexterm>
+ </term>
+ <listitem>
+ <para>Suppress the printing of type coercions.</para>