From: Simon Marlow <simonmar@microsoft.com>
Date: Wed, 30 Aug 2006 08:33:11 +0000 (+0000)
Subject: FILL_SLOP: don't fill slop for BLACKHOLE/CAF_BLACKHOLE
X-Git-Tag: Before_FC_branch_merge~105
X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=commitdiff_plain;h=6f4b74278025a9b8061df721ab4769ae2ea8f2ff

FILL_SLOP: don't fill slop for BLACKHOLE/CAF_BLACKHOLE
This affects -debug only, avoids crash with test conc012.
---

diff --git a/rts/Updates.h b/rts/Updates.h
index 2456f12..abca788 100644
--- a/rts/Updates.h
+++ b/rts/Updates.h
@@ -233,6 +233,10 @@ FILL_SLOP(StgClosure *p)
     switch (inf->type) {
     case BLACKHOLE:
     case CAF_BLACKHOLE:
+	goto no_slop;
+	// we already filled in the slop when we overwrote the thunk
+	// with BLACKHOLE, and also an evacuated BLACKHOLE is only the
+	// size of an IND.
     case THUNK_SELECTOR:
 	sz = sizeofW(StgSelector) - sizeofW(StgThunkHeader);
 	break;
@@ -249,6 +253,8 @@ FILL_SLOP(StgClosure *p)
     for (i = 0; i < sz; i++) {
 	((StgThunk *)p)->payload[i] = 0;
     }
+no_slop:
+    ;
 }
 
 #endif /* CMINUSMINUS */