Add "native" as a valid option value for -march= on arm (PR driver/83193).

2018-02-21  Martin Liska  <mliska@suse.cz>

	PR driver/83193
	* common/config/arm/arm-common.c (arm_print_hint_for_arch_option):
	Add "native" as a possible value.
	* config/arm/arm.h (HAVE_LOCAL_CPU_DETECT): Define the macro
	when native cpu detection is available.

From-SVN: r257873

gcc/ChangeLog

+2018-02-21  Martin Liska  <mliska@suse.cz>
+
+	PR driver/83193
+	* common/config/arm/arm-common.c (arm_print_hint_for_arch_option):
+	Add "native" as a possible value.
+	* config/arm/arm.h (HAVE_LOCAL_CPU_DETECT): Define the macro
+	when native cpu detection is available.
+
 2018-02-21  Jakub Jelinek  <jakub@redhat.com>
 	    Martin Sebor  <msebor@redhat.com>
 

gcc/common/config/arm/arm-common.c

@@ -353,6 +353,12 @@ arm_print_hint_for_arch_option (const char *target,
   auto_vec<const char*> candidates;
   for (; list->common.name != NULL; list++)
     candidates.safe_push (list->common.name);
+
+#ifdef HAVE_LOCAL_CPU_DETECT
+  /* Add also "native" as possible value.  */
+  candidates.safe_push ("native");
+#endif
+
   char *s;
   const char *hint = candidates_list_and_hint (target, s, candidates);
   if (hint)

gcc/config/arm/arm.h

@@ -2194,6 +2194,7 @@ extern const char *arm_target_thumb_only (int argc, const char **argv);
    an ARM chip.  */
 #if defined(__arm__)
 extern const char *host_detect_local_cpu (int argc, const char **argv);
+#define HAVE_LOCAL_CPU_DETECT
 # define MCPU_MTUNE_NATIVE_FUNCTIONS			\
   { "local_cpu_detect", host_detect_local_cpu },
 # define MCPU_MTUNE_NATIVE_SPECS				\