fix: parse negative integer literals

compiler/noirc_frontend/src/parser/parser.rs

@@ -1684,10 +1684,22 @@ fn literal() -> impl NoirParser<ExpressionKind> {
     })
 }
 
+fn literal_with_sign() -> impl NoirParser<ExpressionKind> {
+    choice((
+        literal(),
+        just(Token::Minus).then(literal()).map(|(_, exp)| match exp {
+            ExpressionKind::Literal(Literal::Integer(value, sign)) => {
+                ExpressionKind::Literal(Literal::Integer(value, !sign))
+            }
+            _ => unreachable!(),
+        }),
+    ))
+}
+
 fn literal_or_collection<'a>(
     expr_parser: impl ExprParser + 'a,
 ) -> impl NoirParser<ExpressionKind> + 'a {
-    choice((literal(), constructor(expr_parser.clone()), array_expr(expr_parser)))
+    choice((literal_with_sign(), constructor(expr_parser.clone()), array_expr(expr_parser)))
 }
 
 #[cfg(test)]

test_programs/execution_success/regression_2660/Nargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "regression_2660"
+version = "0.1.0"
+type = "bin"
+authors = [""]
+
+[dependencies]

test_programs/execution_success/regression_2660/Prover.toml

@@ -0,0 +1 @@
+x = "1"

test_programs/execution_success/regression_2660/src/main.nr

@@ -0,0 +1,6 @@
+global foo = -1;
+
+fn main(x: i32) {
+    let y = x + foo;
+    assert(y == 0);
+}