diff options
Diffstat (limited to '0005-doom-Avoid-overflow-for-spawn-angle-calculation.patch')
| -rw-r--r-- | 0005-doom-Avoid-overflow-for-spawn-angle-calculation.patch | 62 |
1 files changed, 0 insertions, 62 deletions
diff --git a/0005-doom-Avoid-overflow-for-spawn-angle-calculation.patch b/0005-doom-Avoid-overflow-for-spawn-angle-calculation.patch deleted file mode 100644 index 94214d8ad13b..000000000000 --- a/0005-doom-Avoid-overflow-for-spawn-angle-calculation.patch +++ /dev/null @@ -1,62 +0,0 @@ -From 7d884d24adff82c020c2663c9142b38ee189ddef Mon Sep 17 00:00:00 2001 -From: Simon Howard <fraggle@soulsphere.org> -Date: Sat, 11 Jul 2015 03:38:49 -0400 -Subject: [PATCH 05/13] doom: Avoid overflow for spawn angle calculation. - -Integer overflow is undefined and this breaks when using Clang with --O2 optimization turned on. This fixes #572 (thanks to David Majnemer -for insight into fixing this bug). ---- - src/doom/g_game.c | 17 ++++++++--------- - 1 file changed, 8 insertions(+), 9 deletions(-) - -diff --git a/src/doom/g_game.c b/src/doom/g_game.c -index bc582a5..3001e03 100644 ---- a/src/doom/g_game.c -+++ b/src/doom/g_game.c -@@ -1168,26 +1168,26 @@ G_CheckSpot - fixed_t xa, ya; - signed int an; - -- an = (ANG45 * ((signed int) mthing->angle / 45)); -- // Right-shifting a negative signed integer is implementation-defined, -- // so divide instead. -- an /= 1 << ANGLETOFINESHIFT; -+ // This calculation overflows in Vanilla Doom, but here we deliberately -+ // avoid integer overflow as it is undefined behavior, so the value of -+ // 'an' will always be positive. -+ an = (ANG45 >> ANGLETOFINESHIFT) * ((signed int) mthing->angle / 45); - - switch (an) - { -- case -4096: -+ case 4096: // -4096: - xa = finetangent[2048]; // finecosine[-4096] - ya = finetangent[0]; // finesine[-4096] - break; -- case -3072: -+ case 5120: // -3072: - xa = finetangent[3072]; // finecosine[-3072] - ya = finetangent[1024]; // finesine[-3072] - break; -- case -2048: -+ case 6144: // -2048: - xa = finesine[0]; // finecosine[-2048] - ya = finetangent[2048]; // finesine[-2048] - break; -- case -1024: -+ case 7168: // -1024: - xa = finesine[1024]; // finecosine[-1024] - ya = finetangent[3072]; // finesine[-1024] - break; -@@ -1195,7 +1195,6 @@ G_CheckSpot - case 1024: - case 2048: - case 3072: -- case 4096: - xa = finecosine[an]; - ya = finesine[an]; - break; --- -2.5.0 - |