SCI32: Allow format strings with missing arguments

SSCI created a fake va_list and passed it to vsprintf, so extra
placeholders would just silently end up reading garbage memory.

1 files changed, 5 insertions, 2 deletions

diff --git a/engines/sci/engine/kstring.cpp b/engines/sci/engine/kstring.cpp
index bfabbcc90e..74c1f99778 100644
--- a/engines/sci/engine/kstring.cpp
+++ b/engines/sci/engine/kstring.cpp
@@ -806,8 +806,11 @@ Common::String format(const Common::String &source, int argc, const reg_t *argv)
 				continue;
 			}
 
-			assert(argIndex < argc);
-			out += readPlaceholder(in, argv[argIndex++]);
+			if (argIndex < argc) {
+				out += readPlaceholder(in, argv[argIndex++]);
+			} else {
+				out += readPlaceholder(in, NULL_REG);
+			}
 		} else {
 			out += *in++;
 		}