fix crash found by fuzzer

build.zig

@@ -45,7 +45,7 @@ pub fn build(b: *std.Build) !void {
         .root_source_file = b.path("src/fuzz/afl.zig"),
         // .target = b.resolveTargetQuery(.{ .cpu_model = .baseline }),
         .target = target,
-        .optimize = .ReleaseSafe,
+        .optimize = .Debug,
         .single_threaded = true,
     });
 

build.zig.zon

@@ -3,7 +3,7 @@
     .version = "0.1.0",
     .dependencies = .{
         .@"zig-afl-kit" = .{
-            .url = "git+https://github.com/kristoff-it/zig-afl-kit#40acb13fc69c155996e34ea06fb651f9389ec2cd",
+            .url = "git+https://github.com/kristoff-it/zig-afl-kit#f003bfe714f2964c90939fdc940d5993190a66ec",
             .hash = "1220f2d8402bb7bbc4786b9c0aad73910929ea209cbd3b063842371d68abfed33c1e",
         },
     },

src/Parser.zig

@@ -46,6 +46,8 @@ pub fn next(p: *Parser, code: []const u8) ?Node {
 
     var path_segments: u32 = 0;
 
+    // if (p.call_depth == 1) @breakpoint();
+
     while (p.it.next(code)) |tok| switch (p.state) {
         .syntax => unreachable,
         .start => switch (tok.tag) {
@@ -87,12 +89,12 @@ pub fn next(p: *Parser, code: []const u8) ?Node {
                 path_segments += 1;
             },
             .lparen => {
-                if (path_segments == 0) {
+                if (path_segments < 2) {
                     p.state = .syntax;
                     return .{ .tag = .syntax_error, .loc = tok.loc };
                 }
 
-                // roll back to get a a lparen
+                // rewind to get a a lparen
                 p.it.idx -= 1;
                 p.state = .call_begin;
                 if (path_segments > 1) {

src/vm.zig

@@ -138,6 +138,7 @@ pub fn VM(
                     }),
                     .call => {
                         // std.debug.assert(vm.stack.len > 0);
+                        // @breakpoint();
                         if (vm.stack.len == 0) {
                             vm.reset();
                             return .{