Add guard entry to asin table.

There was a potential off-end access if the operand to asin()/acos() was exactly 1.

Author: icosahedral-dragon

Diff for: src/Libraries/FIX/Source/MakeTables.c

@@ -84,10 +84,13 @@ uint16_t sintab[256+64+1] = {
 // Its units are fixangs.
 //
 // acos(x) = PI/2 - asin(x).   (PI/2 is fixang 0x4000)
+// Note that there are 130 entries in the table. The asin and acos functions
+// will use the low 8 bits to interpolate between entry i and entry i+1: if the
+// parameter is exactly 1, this will be asintab[128] and asintab[129].
 
 // indexed by (high 8 bits of (fix >> 2 + 0x4000)
 // clang-format off
-fixang asintab[128+1] = {
+fixang asintab[128+1+1] = {
 	0xc001, 0xc737, 0xca37, 0xcc87, 0xce7c, 0xd037, 0xd1ca, 0xd33d, 
 	0xd498, 0xd5e0, 0xd716, 0xd840, 0xd95d, 0xda6f, 0xdb78, 0xdc7a, 
 	0xdd73, 0xde67, 0xdf54, 0xe03c, 0xe11e, 0xe1fd, 0xe2d7, 0xe3ad, 
@@ -104,7 +107,7 @@ fixang asintab[128+1] = {
 	0x1b82, 0x1c54, 0x1d2a, 0x1e04, 0x1ee3, 0x1fc5, 0x20ad, 0x219a, 
 	0x228e, 0x2387, 0x2489, 0x2592, 0x26a4, 0x27c1, 0x28eb, 0x2a21, 
 	0x2b69, 0x2cc4, 0x2e37, 0x2fca, 0x3185, 0x337a, 0x35ca, 0x38ca, 
-	0x4000
+	0x4000, 0x4000
 };
 // clang-format on
 

Diff for: src/Libraries/FIX/Source/trigtab.h

@@ -18,7 +18,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 extern uint16_t sintab[256 + 64 + 1];
 
-extern fixang asintab[128 + 1];
+extern fixang asintab[128 + 1 + 1];
 
 #define INTEGER_EXP_OFFSET 11
 extern uint32_t expinttab[INTEGER_EXP_OFFSET * 2 + 1];