Remove cleanups from check_fast_tracepoint_sals

This changes the gdbarch fast_tracepoint_valid_at method to use a
std::string as its out parameter, and then updates all the uses.  This
allows removing a cleanup from breakpoint.c.

Regression tested by the buildbot.

ChangeLog
2018-02-24  Tom Tromey  <tom@tromey.com>

	* i386-tdep.c (i386_fast_tracepoint_valid_at): "msg" now a
	std::string.
	* gdbarch.sh (fast_tracepoint_valid_at): Change "msg" to a
	std::string*.
	* gdbarch.c: Rebuild.
	* gdbarch.h: Rebuild.
	* breakpoint.c (check_fast_tracepoint_sals): Use std::string.
	* arch-utils.h (default_fast_tracepoint_valid_at): Update.
	* arch-utils.c (default_fast_tracepoint_valid_at): "msg" now a
	std::string*.

1 files changed, 3 insertions, 11 deletions

diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index 91ecca6..c56084c 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -9177,10 +9177,6 @@ static void
 check_fast_tracepoint_sals (struct gdbarch *gdbarch,
 			    gdb::array_view<const symtab_and_line> sals)
 {
-  int rslt;
-  char *msg;
-  struct cleanup *old_chain;
-
   for (const auto &sal : sals)
     {
       struct gdbarch *sarch;
@@ -9190,14 +9186,10 @@ check_fast_tracepoint_sals (struct gdbarch *gdbarch,
 	 associated with SAL.  */
       if (sarch == NULL)
 	sarch = gdbarch;
-      rslt = gdbarch_fast_tracepoint_valid_at (sarch, sal.pc, &msg);
-      old_chain = make_cleanup (xfree, msg);
-
-      if (!rslt)
+      std::string msg;
+      if (!gdbarch_fast_tracepoint_valid_at (sarch, sal.pc, &msg))
 	error (_("May not have a fast tracepoint at %s%s"),
-	       paddress (sarch, sal.pc), (msg ? msg : ""));
-
-      do_cleanups (old_chain);
+	       paddress (sarch, sal.pc), msg.c_str ());
     }
 }