Merge remote-tracking branch 'public/require_some_c99'

3 files changed, 38 insertions, 7 deletions

diff --git a/changes/require-c99 b/changes/require-c99
new file mode 100644
index 0000000000..61d961273a
--- /dev/null
+++ b/changes/require-c99
@@ -0,0 +1,10 @@
+  o New compiler requirements:
+    - Tor 0.2.6.x requires that your compiler support more of the C99
+      language standard than before. The 'configure' script now detects
+      whether your compiler supports C99 mid-block declarations and
+      designated initializers. If it does not, Tor will not compile.
+
+      We may revisit this requirement if it turns out that a significant
+      number of people need to build Tor with compilers that don't
+      bother implementing a 15-year-old standard. Closes ticket 13233.
+
diff --git a/configure.ac b/configure.ac
index 3d35099639..bd46a7c662 100644
--- a/configure.ac
+++ b/configure.ac
@@ -194,6 +194,7 @@ AM_CONDITIONAL(USE_FW_HELPER, test x$natpmp = xtrue || test x$upnp = xtrue)
 AM_CONDITIONAL(NAT_PMP, test x$natpmp = xtrue)
 AM_CONDITIONAL(MINIUPNPC, test x$upnp = xtrue)
 AM_PROG_CC_C_O
+AC_PROG_CC_C99
 
 AC_ARG_VAR(PYTHON)
 AC_CHECK_PROGS(PYTHON, [python python2 python2.7 python3 python3.3])
@@ -224,6 +225,28 @@ AC_C_FLEXIBLE_ARRAY_MEMBER
  fi
 ])
 
+AC_CACHE_CHECK([for working C99 mid-block declaration syntax],
+      tor_cv_c_c99_decl,
+      [AC_COMPILE_IFELSE(
+         [AC_LANG_PROGRAM([], [int x; x = 3; int y; y = 4 + x;])],
+	 [tor_cv_c_c99_decl=yes],
+	 [tor_cv_c_c99_decl=no] )])
+if test "$tor_cv_c_c99_decl" != "yes"; then
+  AC_MSG_ERROR([Your compiler doesn't support c99 mid-block declarations. This is required as of Tor 0.2.6.x])
+fi
+
+AC_CACHE_CHECK([for working C99 designated initializers],
+      tor_cv_c_c99_designated_init,
+      [AC_COMPILE_IFELSE(
+         [AC_LANG_PROGRAM([struct s { int a; int b; };],
+  	       [[ struct s ss = { .b = 5, .a = 6 }; ]])],
+	 [tor_cv_c_c99_designated_init=yes],
+	 [tor_cv_c_c99_designated_init=no] )])
+
+if test "$tor_cv_c_c99_designated_init" != "yes"; then
+  AC_MSG_ERROR([Your compiler doesn't support c99 designated initializers. This is required as of Tor 0.2.6.x])
+fi
+
 AC_PATH_PROG([SHA1SUM], [sha1sum], none)
 AC_PATH_PROG([OPENSSL], [openssl], none)
 
@@ -1511,7 +1534,7 @@ if test x$enable_gcc_warnings = xyes || test x$enable_gcc_warnings_advisory = xy
 
   if test x$have_gcc4 = xyes ; then
     # These warnings break gcc 3.3.5 and work on gcc 4.0.2
-    CFLAGS="$CFLAGS -Winit-self -Wmissing-field-initializers -Wdeclaration-after-statement -Wold-style-definition"
+    CFLAGS="$CFLAGS -Winit-self -Wmissing-field-initializers -Wold-style-definition"
   fi
 
   if test x$have_gcc42 = xyes ; then
diff --git a/src/common/address.c b/src/common/address.c
index 3a78f0be55..07b76597da 100644
--- a/src/common/address.c
+++ b/src/common/address.c
@@ -323,10 +323,9 @@ tor_addr_is_internal_(const tor_addr_t *addr, int for_listening,
 {
   uint32_t iph4 = 0;
   uint32_t iph6[4];
-  sa_family_t v_family;
 
   tor_assert(addr);
-  v_family = tor_addr_family(addr);
+  sa_family_t v_family = tor_addr_family(addr);
 
   if (v_family == AF_INET) {
     iph4 = tor_addr_to_ipv4h(addr);
@@ -472,7 +471,6 @@ tor_addr_parse_PTR_name(tor_addr_t *result, const char *address,
 
   if (!strcasecmpend(address, ".ip6.arpa")) {
     const char *cp;
-    int i;
     int n0, n1;
     struct in6_addr in6;
 
@@ -480,7 +478,7 @@ tor_addr_parse_PTR_name(tor_addr_t *result, const char *address,
       return -1;
 
     cp = address;
-    for (i = 0; i < 16; ++i) {
+    for (int i = 0; i < 16; ++i) {
       n0 = hex_decode_digit(*cp++); /* The low-order nybble appears first. */
       if (*cp++ != '.') return -1;  /* Then a dot. */
       n1 = hex_decode_digit(*cp++); /* The high-order nybble appears first. */
@@ -605,7 +603,7 @@ tor_addr_parse_mask_ports(const char *s,
   int any_flag=0, v4map=0;
   sa_family_t family;
   struct in6_addr in6_tmp;
-  struct in_addr in_tmp;
+  struct in_addr in_tmp = { .s_addr = 0 };
 
   tor_assert(s);
   tor_assert(addr_out);
@@ -666,7 +664,7 @@ tor_addr_parse_mask_ports(const char *s,
     tor_addr_from_ipv4h(addr_out, 0);
     any_flag = 1;
   } else if (!strcmp(address, "*6") && (flags & TAPMP_EXTENDED_STAR)) {
-    static char nil_bytes[16] = { 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0 };
+    static char nil_bytes[16] = { [0]=0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0 };
     family = AF_INET6;
     tor_addr_from_ipv6_bytes(addr_out, nil_bytes);
     any_flag = 1;