gdb/

	Support resolution of STT_GNU_IFUNC via breakpoints.
	* breakpoint.c (print_it_typical): Support bp_gnu_ifunc_resolver and
	bp_gnu_ifunc_resolver_return.
	(bpstat_what): Rename parameter to bs_head, new variable bs, adjust
	the loop.  Support bp_gnu_ifunc_resolver and
	bp_gnu_ifunc_resolver_return.  New comment after the loop.  New loop
	for bp_gnu_ifunc_resolver and bp_gnu_ifunc_resolver_return
	breakpoints.
	(bptype_string, print_one_breakpoint_location): Support
	bp_gnu_ifunc_resolver and bp_gnu_ifunc_resolver_return.
	(user_settable_breakpoint): Return true also for
	bp_gnu_ifunc_resolver.
	(allocate_bp_location): Support bp_gnu_ifunc_resolver and
	bp_gnu_ifunc_resolver_return.
	(set_breakpoint_location_function): New parameter explicit_loc,
	describe it.  Call find_pc_partial_function_gnu_ifunc with new
	variable IS_GNU_IFUNC and adjust the address for STT_GNU_IFUNC if
	EXPLICIT_LOC is not set.
	(set_raw_breakpoint): Set EXPLICIT_LOC for
	set_breakpoint_location_function.
	(clone_momentary_breakpoint): Use true for EXPLICIT_LOC of
	set_breakpoint_location_function.
	(mention): Support bp_gnu_ifunc_resolver and
	bp_gnu_ifunc_resolver_return.
	(add_location_to_breakpoint): Set EXPLICIT_LOC for
	set_breakpoint_location_function.
	(update_breakpoint_locations): Remove static.
	(breakpoint_re_set_one): Support bp_gnu_ifunc_resolver and
	bp_gnu_ifunc_resolver_return.
	* breakpoint.h (enum bptype): New fields bp_gnu_ifunc_resolver and
	bp_gnu_ifunc_resolver_return.
	(update_breakpoint_locations): New declaration.
	* elfread.c: Include gdbthread.h and regcache.h.
	(elf_gnu_ifunc_resolver_stop, elf_gnu_ifunc_resolver_return_stop): New
	functions.
	(elf_gnu_ifunc_fns): Install them.
	* minsyms.c (stub_gnu_ifunc_resolver_stop)
	(stub_gnu_ifunc_resolver_return_stop): New functions.
	(stub_gnu_ifunc_fns): Install them.
	* symtab.h (struct gnu_ifunc_fns): New fields gnu_ifunc_resolver_stop
	and gnu_ifunc_resolver_return_stop.
	(gnu_ifunc_resolver_stop, gnu_ifunc_resolver_return_stop): New.

1 files changed, 16 insertions, 0 deletions

diff --git a/gdb/breakpoint.h b/gdb/breakpoint.h
index d5af928..2cb56b7 100644
--- a/gdb/breakpoint.h
+++ b/gdb/breakpoint.h
@@ -149,6 +149,19 @@ enum bptype
 
     /* Event for JIT compiled code generation or deletion.  */
     bp_jit_event,
+
+    /* Breakpoint is placed at the STT_GNU_IFUNC resolver.  When hit GDB
+       inserts new bp_gnu_ifunc_resolver_return at the caller.
+       bp_gnu_ifunc_resolver is still being kept here as a different thread
+       may still hit it before bp_gnu_ifunc_resolver_return is hit by the
+       original thread.  */
+    bp_gnu_ifunc_resolver,
+
+    /* On its hit GDB now know the resolved address of the target
+       STT_GNU_IFUNC function.  Associated bp_gnu_ifunc_resolver can be
+       deleted now and the breakpoint moved to the target function entry
+       point.  */
+    bp_gnu_ifunc_resolver_return,
   };
 
 /* States of enablement of breakpoint.  */
@@ -890,6 +903,9 @@ extern int breakpoint_thread_match (struct address_space *,
 
 extern void until_break_command (char *, int, int);
 
+extern void update_breakpoint_locations (struct breakpoint *b,
+					 struct symtabs_and_lines sals);
+
 extern void breakpoint_re_set (void);
 
 extern void breakpoint_re_set_thread (struct breakpoint *);