expr: Fix compiler warning on older gcc

jim/jim.c: In function ‘SetExprFromAny’:
jim/jim.c:9109:16: error: ‘top’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
     expr->expr = top;
                ^
jim/jim.c:9075:25: note: ‘top’ was declared here
     struct JimExprNode *top;

Signed-off-by: Steve Bennett <steveb@workware.net.au>

1 files changed, 1 insertions, 1 deletions

diff --git a/jim.c b/jim.c
index 2d16e55..79f126c 100644
--- a/jim.c
+++ b/jim.c
@@ -9070,7 +9070,7 @@ static struct ExprTree *ExprTreeCreateTree(Jim_Interp *interp, const ParseTokenL
     struct ExprTree *expr;
     struct ExprBuilder builder;
     int rc;
-    struct JimExprNode *top;
+    struct JimExprNode *top = NULL;
 
     builder.parencount = 0;
     builder.level = 0;