>From 845ff6dbb4fcaff7fc5f5422f33d8d3a99a2a108 Mon Sep 17 00:00:00 2001
From: Andreas Stieger <astieger@suse.com>
Date: Sun, 28 May 2017 23:49:31 +0200
Subject: [PATCH] Fix GCC 7 -Wimplicit-fallthrough warnings

Add magic comments recognized by default -Wimplicit-fallthrough=3
or break, as required.
---
 src/ext/csiphash.c                       | 14 +++++++-------
 src/ext/ed25519/donna/modm-donna-64bit.h | 24 ++++++++++++------------
 src/or/buffers.c                         |  1 +
 src/or/connection_edge.c                 |  1 +
 src/or/dns.c                             |  1 +
 src/or/relay.c                           |  1 +
 6 files changed, 23 insertions(+), 19 deletions(-)

diff --git a/src/ext/csiphash.c b/src/ext/csiphash.c
index 1029bbbad..508e4f6ce 100644
--- a/src/ext/csiphash.c
+++ b/src/ext/csiphash.c
@@ -88,13 +88,13 @@ uint64_t siphash24(const void *src, unsigned long src_sz, const struct sipkey *k
 	}
 
 	switch (src_sz - blocks) {
-		case 7: last7 |= (uint64_t)m[i + 6] << 48;
-		case 6: last7 |= (uint64_t)m[i + 5] << 40;
-		case 5: last7 |= (uint64_t)m[i + 4] << 32;
-		case 4: last7 |= (uint64_t)m[i + 3] << 24;
-		case 3: last7 |= (uint64_t)m[i + 2] << 16;
-		case 2: last7 |= (uint64_t)m[i + 1] <<  8;
-		case 1: last7 |= (uint64_t)m[i + 0]      ;
+		case 7: last7 |= (uint64_t)m[i + 6] << 48; /* Falls through. */
+		case 6: last7 |= (uint64_t)m[i + 5] << 40; /* Falls through. */
+		case 5:	last7 |= (uint64_t)m[i + 4] << 32; /* Falls through. */
+		case 4: last7 |= (uint64_t)m[i + 3] << 24; /* Falls through. */
+		case 3:	last7 |= (uint64_t)m[i + 2] << 16; /* Falls through. */
+		case 2:	last7 |= (uint64_t)m[i + 1] <<  8; /* Falls through. */
+		case 1: last7 |= (uint64_t)m[i + 0]      ; /* Falls through. */
 		case 0:
 		default:;
 	}
diff --git a/src/ext/ed25519/donna/modm-donna-64bit.h b/src/ext/ed25519/donna/modm-donna-64bit.h
index 012ea9ea0..06c98e303 100644
--- a/src/ext/ed25519/donna/modm-donna-64bit.h
+++ b/src/ext/ed25519/donna/modm-donna-64bit.h
@@ -294,10 +294,10 @@ sub256_modm_batch(bignum256modm out, const bignum256modm a, const bignum256modm
 	size_t i = 0;
 	bignum256modm_element_t carry = 0;
 	switch (limbsize) {
-		case 4: out[i] = (a[i] - b[i])        ; carry = (out[i] >> 63); out[i] &= 0xffffffffffffff; i++;
-		case 3: out[i] = (a[i] - b[i]) - carry; carry = (out[i] >> 63); out[i] &= 0xffffffffffffff; i++;
-		case 2: out[i] = (a[i] - b[i]) - carry; carry = (out[i] >> 63); out[i] &= 0xffffffffffffff; i++;
-		case 1: out[i] = (a[i] - b[i]) - carry; carry = (out[i] >> 63); out[i] &= 0xffffffffffffff; i++;
+		case 4: out[i] = (a[i] - b[i])        ; carry = (out[i] >> 63); out[i] &= 0xffffffffffffff; i++; /* Falls through. */
+		case 3: out[i] = (a[i] - b[i]) - carry; carry = (out[i] >> 63); out[i] &= 0xffffffffffffff; i++; /* Falls through. */
+		case 2:	out[i] = (a[i] - b[i]) - carry; carry = (out[i] >> 63); out[i] &= 0xffffffffffffff; i++; /* Falls through. */
+		case 1:	out[i] = (a[i] - b[i]) - carry; carry = (out[i] >> 63); out[i] &= 0xffffffffffffff; i++; /* Falls through. */
 		case 0: 
 		default: out[i] = (a[i] - b[i]) - carry;
 	}
@@ -310,10 +310,10 @@ lt256_modm_batch(const bignum256modm a, const bignum256modm b, size_t limbsize)
 	size_t i = 0;
 	bignum256modm_element_t t, carry = 0;
 	switch (limbsize) {
-		case 4: t = (a[i] - b[i])        ; carry = (t >> 63); i++;
-		case 3: t = (a[i] - b[i]) - carry; carry = (t >> 63); i++;
-		case 2: t = (a[i] - b[i]) - carry; carry = (t >> 63); i++;
-		case 1: t = (a[i] - b[i]) - carry; carry = (t >> 63); i++;
+		case 4: t = (a[i] - b[i])        ; carry = (t >> 63); i++; /* Falls through. */
+		case 3: t = (a[i] - b[i]) - carry; carry = (t >> 63); i++; /* Falls through. */
+		case 2: t = (a[i] - b[i]) - carry; carry = (t >> 63); i++; /* Falls through. */
+		case 1: t = (a[i] - b[i]) - carry; carry = (t >> 63); i++; /* Falls through. */
 		case 0: t = (a[i] - b[i]) - carry; carry = (t >> 63);
 	}
 	return (int)carry;
@@ -325,10 +325,10 @@ lte256_modm_batch(const bignum256modm a, const bignum256modm b, size_t limbsize)
 	size_t i = 0;
 	bignum256modm_element_t t, carry = 0;
 	switch (limbsize) {
-		case 4: t = (b[i] - a[i])        ; carry = (t >> 63); i++;
-		case 3: t = (b[i] - a[i]) - carry; carry = (t >> 63); i++;
-		case 2: t = (b[i] - a[i]) - carry; carry = (t >> 63); i++;
-		case 1: t = (b[i] - a[i]) - carry; carry = (t >> 63); i++;
+		case 4: t = (b[i] - a[i])        ; carry = (t >> 63); i++; /* Falls through. */
+		case 3: t = (b[i] - a[i]) - carry; carry = (t >> 63); i++; /* Falls through. */
+		case 2: t = (b[i] - a[i]) - carry; carry = (t >> 63); i++; /* Falls through. */
+		case 1: t = (b[i] - a[i]) - carry; carry = (t >> 63); i++; /* Falls through. */
 		case 0: t = (b[i] - a[i]) - carry; carry = (t >> 63);
 	}
 	return (int)!carry;
diff --git a/src/or/buffers.c b/src/or/buffers.c
index 58cfdeee8..3692ed4d0 100644
--- a/src/or/buffers.c
+++ b/src/or/buffers.c
@@ -1715,6 +1715,7 @@ parse_socks(const char *data, size_t datalen, socks_request_t *req,
           return -1;
       }
       tor_assert(0);
+      break;
     case 4: { /* socks4 */
       enum {socks4, socks4a} socks4_prot = socks4a;
       const char *authstart, *authend;
diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c
index fd9c97bd3..fc1b2c3bb 100644
--- a/src/or/connection_edge.c
+++ b/src/or/connection_edge.c
@@ -261,6 +261,7 @@ connection_edge_process_inbuf(edge_connection_t *conn, int package_partial)
       }
       /* Fall through if the connection is on a circuit without optimistic
        * data support. */
+      /* Falls through. */
     case EXIT_CONN_STATE_CONNECTING:
     case AP_CONN_STATE_RENDDESC_WAIT:
     case AP_CONN_STATE_CIRCUIT_WAIT:
diff --git a/src/or/dns.c b/src/or/dns.c
index 8a40a70d7..98b684c90 100644
--- a/src/or/dns.c
+++ b/src/or/dns.c
@@ -523,6 +523,7 @@ send_resolved_cell,(edge_connection_t *conn, uint8_t answer_type,
         answer_type = RESOLVED_TYPE_ERROR;
         /* fall through. */
       }
+      /* Falls through. */
     case RESOLVED_TYPE_ERROR_TRANSIENT:
     case RESOLVED_TYPE_ERROR:
       {
diff --git a/src/or/relay.c b/src/or/relay.c
index 7082002f8..c119c3df1 100644
--- a/src/or/relay.c
+++ b/src/or/relay.c
@@ -994,6 +994,7 @@ connection_ap_process_end_not_open(
           break; /* break means it'll close, below */
         /* Else fall through: expire this circuit, clear the
          * chosen_exit_name field, and try again. */
+        /* Falls through. */
       case END_STREAM_REASON_RESOLVEFAILED:
       case END_STREAM_REASON_TIMEOUT:
       case END_STREAM_REASON_MISC:
-- 
2.13.0

