ref: e15a2defff30a00562800d1b6248a4b65f919e15
parent: 74f45138aeb6608137344c7d5245ff6e3ec12572
author: Simon Tatham <anakin@pobox.com>
date: Mon Dec 26 18:24:09 EST 2005
Laurent Thioudellet reports that gcc4's ultra-cautious data flow warnings require two more variables to be explicitly initialised. In fact these variables are reliably initialised by a subfunction; gcc3 was happy to assume I knew what I was doing when it couldn't prove they were definitely used uninitialised, whereas gcc4 apparently takes the view that the onus is on me to allow it to prove they _aren't_. I regard this as a step backwards, since the effect will be to make explicit initialisation commonplace in cases where the initialiser value is chosen arbitrarily and never expected to be used, at which point (a) it will be less clear which initialisers have genuine purpose and which are compiler-placating fluff, and (b) valgrind's run-time uninitialised-data tracking will become less useful. Still, the effect doesn't seem great as yet, so here's the gcc4-placating checkin. [originally from svn r6508]
--- a/bridges.c
+++ b/bridges.c
@@ -1012,7 +1012,7 @@
static int map_hasloops(game_state *state, int mark)
{- int x, y, ox, oy, nx, ny, loop = 0;
+ int x, y, ox, oy, nx = 0, ny = 0, loop = 0;
memcpy(state->scratch, state->grid, GRIDSZ(state));