[RFA v2 03/13] Unused variable fixes related to conditional compilation

[Tom Tromey <tom@tromey.com>]

This patch fixes various unused variable warnings that are related to
conditional compilation.  In these cases, either the variable is now
protected by the same #if as its uses, or the declaration is simply
lowered into the conditionally-compiled block.

gdb/ChangeLog
2018-07-21  Tom Tromey  <tom@tromey.com>

	* windows-nat.c (saved_context): Conditionally define.
	* remote.c (remote_target::remote_btrace_maybe_reopen):
	Conditionally declare "warned".
	* inflow.c (sigquit_ours): Conditionally define.
	(new_tty): Move "tty" declaration inside #if.
	* guile/guile.c (guile_datadir): Conditionally define.
	* charset.c (set_be_le_names): Move some declarations inside #if.
	* btrace.c (parse_xml_btrace): Move "errcode" declaration inside
	#if.
	(parse_xml_btrace_conf): Likewise.
---
 gdb/ChangeLog     | 13 +++++++++++++
 gdb/btrace.c      |  6 ++----
 gdb/charset.c     |  6 +++---
 gdb/guile/guile.c |  2 ++
 gdb/inflow.c      |  6 ++++--
 gdb/remote.c      |  2 ++
 gdb/windows-nat.c |  2 ++
 7 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/gdb/btrace.c b/gdb/btrace.c
index 35dc90e8e67..e25f047ce24 100644
--- a/gdb/btrace.c
+++ b/gdb/btrace.c
@@ -2202,10 +2202,9 @@ static const struct gdb_xml_element btrace_elements[] = {
 void
 parse_xml_btrace (struct btrace_data *btrace, const char *buffer)
 {
-  int errcode;
-
 #if defined (HAVE_LIBEXPAT)
 
+  int errcode;
   btrace_data result;
   result.format = BTRACE_FORMAT_NONE;
 
@@ -2303,10 +2302,9 @@ static const struct gdb_xml_element btrace_conf_elements[] = {
 void
 parse_xml_btrace_conf (struct btrace_config *conf, const char *xml)
 {
-  int errcode;
-
 #if defined (HAVE_LIBEXPAT)
 
+  int errcode;
   errcode = gdb_xml_parse_quick (_("btrace-conf"), "btrace-conf.dtd",
 				 btrace_conf_elements, xml, conf);
   if (errcode != 0)
diff --git a/gdb/charset.c b/gdb/charset.c
index fcb24a48823..8bb2b4d669f 100644
--- a/gdb/charset.c
+++ b/gdb/charset.c
@@ -295,9 +295,6 @@ static struct gdbarch *be_le_arch;
 static void
 set_be_le_names (struct gdbarch *gdbarch)
 {
-  int i, len;
-  const char *target_wide;
-
   if (be_le_arch == gdbarch)
     return;
   be_le_arch = gdbarch;
@@ -307,6 +304,9 @@ set_be_le_names (struct gdbarch *gdbarch)
   target_wide_charset_le_name = "UTF-32LE";
   target_wide_charset_be_name = "UTF-32BE";
 #else
+  int i, len;
+  const char *target_wide;
+
   target_wide_charset_le_name = NULL;
   target_wide_charset_be_name = NULL;
 
diff --git a/gdb/guile/guile.c b/gdb/guile/guile.c
index 6353b35326b..95b36febed0 100644
--- a/gdb/guile/guile.c
+++ b/gdb/guile/guile.c
@@ -46,8 +46,10 @@ int gdbscm_guile_major_version;
 int gdbscm_guile_minor_version;
 int gdbscm_guile_micro_version;
 
+#ifdef HAVE_GUILE
 /* The guile subdirectory within gdb's data-directory.  */
 static const char *guile_datadir;
+#endif
 
 /* Declared constants and enum for guile exception printing.  */
 const char gdbscm_print_excp_none[] = "none";
diff --git a/gdb/inflow.c b/gdb/inflow.c
index a3b5ba8abef..caff6462070 100644
--- a/gdb/inflow.c
+++ b/gdb/inflow.c
@@ -138,7 +138,9 @@ private:
    to SIG_IGN.  */
 
 static sighandler_t sigint_ours;
+#ifdef SIGQUIT
 static sighandler_t sigquit_ours;
+#endif
 
 /* The name of the tty (from the `tty' command) that we're giving to
    the inferior when starting it up.  This is only (and should only
@@ -825,11 +827,11 @@ check_syscall (const char *msg, int result)
 void
 new_tty (void)
 {
-  int tty;
-
   if (inferior_thisrun_terminal == 0)
     return;
 #if !defined(__GO32__) && !defined(_WIN32)
+  int tty;
+
 #ifdef TIOCNOTTY
   /* Disconnect the child process from our controlling terminal.  On some
      systems (SVR4 for example), this may cause a SIGTTOU, so temporarily
diff --git a/gdb/remote.c b/gdb/remote.c
index a81d67e5ede..a61680d242c 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -13717,7 +13717,9 @@ remote_target::remote_btrace_maybe_reopen ()
   struct remote_state *rs = get_remote_state ();
   struct thread_info *tp;
   int btrace_target_pushed = 0;
+#if !defined (HAVE_LIBIPT)
   int warned = 0;
+#endif
 
   scoped_restore_current_thread restore_thread;
 
diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
index 3f722a14389..e0e422c0f05 100644
--- a/gdb/windows-nat.c
+++ b/gdb/windows-nat.c
@@ -146,8 +146,10 @@ static GetConsoleFontSize_ftype *GetConsoleFontSize;
 
 static int have_saved_context;	/* True if we've saved context from a
 				   cygwin signal.  */
+#ifdef __CYGWIN__
 static CONTEXT saved_context;	/* Containes the saved context from a
 				   cygwin signal.  */
+#endif
 
 /* If we're not using the old Cygwin header file set, define the
    following which never should have been in the generic Win32 API
-- 
2.13.6