some more info in the QSG

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@4420

diff --git a/docs/xml/quick-start-guide.xml b/docs/xml/quick-start-guide.xml
index b4d2dc93bcce7ac4bb584e8168eed582f694a6b5..c083dcf29ec5738244362cec8db1d4d103e1a104 100644 (file)
--- a/docs/xml/quick-start-guide.xml
+++ b/docs/xml/quick-start-guide.xml
@@ -40,7 +40,10 @@ right for earlier versions.</para>
 <title>Preparing your program</title>
 <para>Compile your program with <computeroutput>-g</computeroutput> to include
 debugging information so that Memcheck's error messages include exact line
-numbers.</para>
+numbers.  Using <computeroutput>-O0</computeroutput> is also a good idea;
+with <computeroutput>-O1</computeroutput> line numbers in error messages can
+be inaccurate, and with <computeroutput>-O2</computeroutput> Memcheck
+occasionally reports undefined error messages incorrectly.</para>
 </sect1>
 
 <sect1 id="quick-start.mcrun"