Expand the first para of the custom-allocator section so it says what

this section actually describes.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@6199

diff --git a/memcheck/docs/mc-manual.xml b/memcheck/docs/mc-manual.xml
index ed2a7142670a8f847da77f9af705710599166a15..8b0ca52191a83f0a039750011a9083646a7edbf7 100644 (file)
--- a/memcheck/docs/mc-manual.xml
+++ b/memcheck/docs/mc-manual.xml
@@ -1080,7 +1080,13 @@ arguments.</para>
 <title>Memory Pools: describing and working with custom allocators</title>
 
 <para>Some programs use custom memory allocators, often for performance
-reasons.  There are many different sorts of memory pool, so Memcheck
+reasons.  Left to itself, Memcheck is unable to "understand" the
+behaviour of custom allocation schemes and so may miss errors and
+leaks in your program.  What this section describes is a way to give
+Memcheck enough of a description of your custom allocator that it can
+make at least some sense of what is happening.</para>
+
+<para>There are many different sorts of custom allocator, so Memcheck
 attempts to reason about them using a loose, abstract model.  We
 use the following terminology when describing custom allocation
 systems:</para>