Fixed a crash in address to line mapping

Author: RPGHacker

src/asar/assembleblock.cpp

@@ -1201,11 +1201,14 @@ void assembleblock(const char * block, bool isspecialline)
 		{
 			// RPG Hacker: This makes a pretty big assumption to calculate the size of opcodes.
 			// However, this should currently only really be used for pseudo opcodes, where it should always be good enough.
-			int opcode_size = ((0xFFFFFF & realsnespos) - addrToLinePos) / recent_opcode_num;
-			for (int i = 0; i < recent_opcode_num; ++i)
+			if (recent_opcode_num > 0)
 			{
-				extern AddressToLineMapping addressToLineMapping;
-				addressToLineMapping.includeMapping(thisfilename.data(), thisline + 1, addrToLinePos + (i * opcode_size));
+				int opcode_size = ((0xFFFFFF & realsnespos) - addrToLinePos) / recent_opcode_num;
+				for (int i = 0; i < recent_opcode_num; ++i)
+				{
+					extern AddressToLineMapping addressToLineMapping;
+					addressToLineMapping.includeMapping(thisfilename.data(), thisline + 1, addrToLinePos + (i * opcode_size));
+				}
 			}
 		}
 		numopcodes += recent_opcode_num;

tests/pseudo-opcodes.asm

@@ -0,0 +1,7 @@
+;`C8 0A 0A 4A 4A 4A
+
+org $008000
+inx #0
+iny #1
+asl #2
+lsr #3