Add test program to verify compile-time error if no type in for-in lo…

…op (#4812)

Signed-off-by: Andy Fingerhut <[email protected]>

testdata/p4_16_errors/loop3-err.p4

@@ -0,0 +1,91 @@
+/*
+Copyright 2024 Andy Fingerhut
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+#include <core.p4>
+#include <v1model.p4>
+
+header ethernet_t {
+    bit<48> dstAddr;
+    bit<48> srcAddr;
+    bit<16> etherType;
+}
+
+struct metadata_t {
+}
+
+struct headers_t {
+    ethernet_t ethernet;
+}
+
+parser parserImpl(packet_in packet,
+                  out headers_t hdr,
+                  inout metadata_t meta,
+                  inout standard_metadata_t stdmeta)
+{
+    state start {
+        packet.extract(hdr.ethernet);
+        transition accept;
+    }
+}
+
+control ingressImpl(inout headers_t hdr,
+                    inout metadata_t meta,
+                    inout standard_metadata_t stdmeta)
+{
+    bit<8> n = 0;
+    bit<8> i = 20;
+    apply {
+        for (i in 1..6) {
+            n = n + i;
+        }
+        hdr.ethernet.srcAddr[15:8] = n;
+        hdr.ethernet.srcAddr[7:0] = i;
+        stdmeta.egress_spec = 1;
+    }
+}
+
+control egressImpl(inout headers_t hdr,
+                   inout metadata_t meta,
+                   inout standard_metadata_t stdmeta)
+{
+    apply {
+    }
+}
+
+control deparserImpl(packet_out packet,
+                     in headers_t hdr)
+{
+    apply {
+        packet.emit(hdr.ethernet);
+    }
+}
+
+control verifyChecksum(inout headers_t hdr, inout metadata_t meta) {
+    apply {
+    }
+}
+
+control updateChecksum(inout headers_t hdr, inout metadata_t meta) {
+    apply {
+    }
+}
+
+V1Switch(parserImpl(),
+         verifyChecksum(),
+         ingressImpl(),
+         egressImpl(),
+         updateChecksum(),
+         deparserImpl()) main;

testdata/p4_16_errors_outputs/loop3-err.p4-stderr

@@ -0,0 +1,4 @@
+loop3-err.p4(51):syntax error, unexpected IN
+        for (i in
+               ^^
+[--Werror=overlimit] error: 1 errors encountered, aborting compilation