diff lwasm/output.c @ 577:e49d24f4a9a5

Correct bug in the object file output code leading to stack corruption It turns out leaving a pointer to a stack allocated temporary in a persistent data structure is not conducive to correct program operation. Undo the export check setup in the object file output sequence so a pointer to stack allocated memory is not left hanging when the function returns. This seems to correct at least one mysterious crash bug, and possibly others. Thanks to Boisy Pitre for reporting the crash bug that led to this discovery, as well as a previous crash bug that likely has the same root cause. Additional thanks to Ciaran Anscomb whose debugger wielding wizardry revealed the exact location of this particular bit of unbrilliance.
author William Astle <lost@l-w.ca>
date Sat, 03 Aug 2024 14:30:06 -0600
parents e10618b48e68
children
line wrap: on
line diff
--- a/lwasm/output.c	Fri Jul 12 23:02:57 2024 -0600
+++ b/lwasm/output.c	Sat Aug 03 14:30:06 2024 -0600
@@ -1000,6 +1000,10 @@
 			buf[0] = (offset >> 8) & 0xff;
 			buf[1] = offset & 0xff;
 			writebytes(buf, 2, 1, of);
+
+			// clean up after ourselves so other stuff doesn't explode
+			as -> cl = NULL;
+			as -> exportcheck = 0;
 		}
 
 		// flag end of incomplete references list