SCI: Zero out dynamically allocated memory

Fixes Mixed Up Mother Goose SCI1.1 crash when saving
And could potentially fix all sorts of other issues
Original SCI only zeroed out heap on init.

1 files changed, 6 insertions, 3 deletions

diff --git a/engines/sci/engine/seg_manager.cpp b/engines/sci/engine/seg_manager.cpp
index 23b1fdae23..8090b1861d 100644
--- a/engines/sci/engine/seg_manager.cpp
+++ b/engines/sci/engine/seg_manager.cpp
@@ -837,10 +837,13 @@ byte *SegManager::allocDynmem(int size, const char *descr, reg_t *addr) {
 
 	d._size = size;
 
-	if (size == 0)
+	// Original SCI only zeroed out heap memory on initialize
+	// They didn't do it again for every allocation
+	if (size) {
+		d._buf = (byte *)calloc(size, 1);
+	} else {
 		d._buf = NULL;
-	else
-		d._buf = (byte *)malloc(size);
+	}
 
 	d._description = descr;