Fix circuits with 0 inputs

Author: jbaylina

ports/wasm/build_runtime.js

@@ -180,6 +180,17 @@ module.exports = function buildRuntime(module, builder) {
         const c = f.getCodeBuilder();
 
         f.addCode(
+            // Don't call it again.  (It is possoble in the init)
+            c.i32_store(
+                c.i32_add(
+                    c.i32_const(builder.pInputSignalsToTrigger),
+                    c.i32_mul(
+                        c.getLocal("component"),
+                        c.i32_const(4)
+                    )
+                ),
+                c.i32_const(-1)
+            ),
             c.call_indirect(
                 c.getLocal("component"),        // Idx in table
                 c.getLocal("component")         // Parameter

test/basiccases.json

@@ -328,5 +328,12 @@
         "tv": [
             [{}, {"out": [3,4]}]
         ]
+    },
+    {
+        "name": "poma2",
+        "circuit": "poma2.circom",
+        "tv": [
+            [{}, {}]
+        ]
     }
 ]

test/circuits/poma2.circom

@@ -0,0 +1,17 @@
+
+
+template sum() {
+  signal input in[2];
+  signal output out;
+  out <== in[0] + in[1];
+}
+
+
+template Test() {
+    component hasher = sum();
+    hasher.in[0] <== 1;
+    hasher.in[1] <== 2;
+}
+
+component main = Test();
+