Add 'getthrds' declaration check in configure for AIX

On newer versions of AIX (6.x and later), this function is actually
declared in procinfo.h, thus causing a compilation warning when we
re-declare it ourselves. This patch adds a configure check for that
function allowing us to declare the function only if the declaration
isn't already present in one of procinfo system header.

gdb/ChangeLog:

        PR gdb/12116:
        * configure.ac: Add getthrds declaration check.
        * configure, config.in: Regenerate.
        * aix-thread.c (getthrds): Declare only if not already declared
        in procinfo.h.  More declaration out of get_signaled_thread to
        global scope.

1 files changed, 16 insertions, 0 deletions

diff --git a/gdb/configure b/gdb/configure
index 5ee5ce6..92818a0 100755
--- a/gdb/configure
+++ b/gdb/configure
@@ -14487,6 +14487,22 @@ $as_echo "$gdb_cv_have_aix_thread_debug" >&6; }
          CONFIG_SRCS="${CONFIG_SRCS} aix-thread.c"
          CONFIG_OBS="${CONFIG_OBS} aix-thread.o"
          CONFIG_LDFLAGS="${CONFIG_LDFLAGS} -lpthdebug"
+
+         # Older versions of AIX do not provide the declaration for
+         # the getthrds function (it appears that it was introduced
+         # with AIX 6.x).
+         ac_fn_c_check_decl "$LINENO" "getthrds" "ac_cv_have_decl_getthrds" "#include <procinfo.h>
+"
+if test "x$ac_cv_have_decl_getthrds" = x""yes; then :
+  ac_have_decl=1
+else
+  ac_have_decl=0
+fi
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_DECL_GETTHRDS $ac_have_decl
+_ACEOF
+
       fi
       ;;
    esac