diff --git a/passes/cmds/abstract.cc b/passes/cmds/abstract.cc
index 1e67dcd88..513cd8ecc 100644
--- a/passes/cmds/abstract.cc
+++ b/passes/cmds/abstract.cc
@@ -45,7 +45,7 @@ struct Slice {
 	}
 
 	static int parse_index(const char *begin, const char *end, const std::string &slice) {
-		int value;
+		int value = 0;
 		auto result = std::from_chars(begin, end, value, 10);
         if (result.ptr != end || result.ptr == begin)
 			syntax_error(slice);