When looking for a heap segment to extend look for the heap limit

address rather than the base address as the heap may have been split
into more than one segment by using mprotect on it...

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@4882

diff --git a/coregrind/m_syswrap/syswrap-generic.c b/coregrind/m_syswrap/syswrap-generic.c
index f4a9cb7e74bd12983e28daa3b199dc02c4140a91..39ce5eab1a8e6d914ec8d3834549465f816a6686 100644 (file)
--- a/coregrind/m_syswrap/syswrap-generic.c
+++ b/coregrind/m_syswrap/syswrap-generic.c
@@ -952,7 +952,10 @@ static Addr do_brk ( Addr newbrk )
    }
 
    /* otherwise we're expanding the brk segment. */
-   aseg = VG_(am_find_nsegment)( VG_(brk_base) );
+   if (VG_(brk_limit) > VG_(brk_base))
+      aseg = VG_(am_find_nsegment)( VG_(brk_limit)-1 );
+   else
+      aseg = VG_(am_find_nsegment)( VG_(brk_limit) );
    rseg = VG_(am_next_nsegment)( aseg, True/*forwards*/ );
 
    /* These should be assured by setup_client_dataseg in m_main. */