[PATCH] Report "No hardware breakpoint support" correctly

[Edjunior Barbosa Machado <emachado@linux.vnet.ibm.com>]

Hi,

when trying to set a hardware breakpoint on Power server processors, gdb
currently reports "Hardware breakpoints used exceeds limit." when in fact
hbreaks are not supported. With this patch, gdb will report "No hardware
breakpoint support in the target.", which seems to be more appropriate in this
case.
This also fixes the several unexpected failures in
gdb.base/watchpoint-reuse-slot.exp testcase, that didn't detect that hbreaks
are not supported in this target.
Ok?

Thanks and regards,
--
Edjunior

gdb/
2014-07-14  Edjunior Barbosa Machado  <emachado@linux.vnet.ibm.com>

	* gdb/ppc-linux-nat.c (ppc_linux_can_use_hw_breakpoint): Report no
	hardware breakpoint support correctly.

---
 gdb/ppc-linux-nat.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/gdb/ppc-linux-nat.c b/gdb/ppc-linux-nat.c
index fcfd452..4c5d878 100644
--- a/gdb/ppc-linux-nat.c
+++ b/gdb/ppc-linux-nat.c
@@ -1473,6 +1473,9 @@ ppc_linux_can_use_hw_breakpoint (struct target_ops *self,
     }
   else if (type == bp_hardware_breakpoint)
     {
+      if (total_hw_bp == 0)
+	/* No hardware breakpoint support. */
+	return 0;
       if (cnt > total_hw_bp)
 	return -1;
     }
-- 
1.8.4.2