From: Julian Seward <jseward@acm.org>
Date: Thu, 29 May 2008 12:23:24 +0000 (+0000)
Subject: In the leak checker, don't assert when there are multiple identical
X-Git-Tag: svn/VALGRIND_3_4_0~541
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=6dbfe6814f8343478dfc866777f466957ebd2672;p=thirdparty%2Fvalgrind.git

In the leak checker, don't assert when there are multiple identical
blocks in the lc_shadows array.  Such a situation could arise from
incorrect use of VALGRIND_MALLOCLIKE_BLOCK, and has been observed to
cause assertion failures for some runs of Wine on Valgrind.



git-svn-id: svn://svn.valgrind.org/valgrind/trunk@8144
---

diff --git a/memcheck/mc_leakcheck.c b/memcheck/mc_leakcheck.c
index c838d3c1b4..a8af9ff05b 100644
--- a/memcheck/mc_leakcheck.c
+++ b/memcheck/mc_leakcheck.c
@@ -694,10 +694,22 @@ void MC_(do_detect_memory_leaks) (
       tl_assert( lc_shadows[i]->data <= lc_shadows[i+1]->data);
    }
 
-   /* Sanity check -- make sure they don't overlap */
+   /* Sanity check -- make sure they don't overlap.  But do allow
+      exact duplicates.  If this assertion fails, it may mean that the
+      application has done something stupid with
+      VALGRIND_MALLOCLIKE_BLOCK client requests, specifically, has
+      made overlapping requests (which are nonsensical).  Another way
+      to screw up is to use VALGRIND_MALLOCLIKE_BLOCK for stack
+      locations; again nonsensical. */
    for (i = 0; i < lc_n_shadows-1; i++) {
-      tl_assert( lc_shadows[i]->data + lc_shadows[i]->szB
-                 <= lc_shadows[i+1]->data );
+      tl_assert( /* normal case - no overlap */
+                 (lc_shadows[i]->data + lc_shadows[i]->szB
+                  <= lc_shadows[i+1]->data )
+                 ||
+                 /* degenerate case: exact duplicates */
+                 (lc_shadows[i]->data == lc_shadows[i+1]->data
+                  && lc_shadows[i]->szB == lc_shadows[i+1]->szB)
+               );
    }
 
    if (lc_n_shadows == 0) {