* sem_ch3.adb (Add_Internal_Interface_Entities): Move
Has_Non_Trivial_Precondition to sem_util. for use elsewhere.
Improve error message on operations that inherit non-conforming
classwide preconditions from ancestor and progenitor.
* sem_util.ads, sem_util.adb (Has_Non_Trivial_Precondition):
moved here from sem_ch3.
* sem_ch8.adb (Analyze_Subprogram_Renaming): Implement legality
check given in RM 6.1.1 (17) concerning renamings of overriding
operations that inherits class-wide preconditions from ancestor
or progenitor.
* exp_ch7.adb (Build_Adjust_Or_Finalize_Statements): Code cleanup.
(Build_Adjust_Statements): Code cleanup.
(Build_Finalizer): Update the initialization of
Exceptions_OK.
(Build_Finalize_Statements): Code cleanup.
(Build_Initialize_Statements): Code cleanup.
(Make_Deep_Array_Body): Update the initialization of
Exceptions_OK.
(Make_Deep_Record_Body): Update the initialization of Exceptions_OK.
(Process_Object_Declaration): Generate a null exception handler only
when exceptions are allowed.
(Process_Transients_In_Scope): Update the initialization of
Exceptions_OK.
* exp_util.ads, exp_util.adb (Exceptions_In_Finalization_OK): New
routine.
* sem_ch11.adb (Analyze_Exception_Handlers): Do not check any
restrictions when the handler is internally generated and the
mode is warnings.
2017-04-25 Ed Schonberg <schonberg@adacore.com>
* sem_ch3.adb (Has_Non_Trivial_Precondition): New predicate to
enforce legality rule on classwide preconditions inherited from
both an ancestor and a progenitor (RM 6.1.1 (10-13).
* sem_disp.adb (Check_Dispatching_Context): A call to an abstract
subprogram need not be dispatching if it appears in a precondition
for an abstract or null subprogram.