Skip to content

R
riscv-gcc-1
Commit ca1f6b29 by Bob Duff Committed by Arnaud Charlet
Options

sem_prag.adb (No_Return): Give an error if the pragma applies to a body. 

2017-04-25  Bob Duff  <duff@adacore.com>

	* sem_prag.adb (No_Return): Give an error if the pragma applies
	to a body. Specialize the error for the specless body case,
	as is done for (e.g.) pragma Convention.
	* debug.adb: Add switch -gnatd.J to disable the above legality
	checks. This is mainly for use in our test suite, to avoid
	rewriting a lot of illegal (but working) code.	It might also
	be useful to customers. Under this switch, if a pragma No_Return
	applies to a body, and the procedure raises an exception (as it
	should), the pragma has no effect. If the procedure does return,
	execution is erroneous.

2017-04-25  Bob Duff  <duff@adacore.com>

	* exp_ch6.adb (Expand_Actuals): This is the
	root of the problem. It took N as an 'in out' parameter, and in
	some cases, rewrote N, but then set N to Original_Node(N). So
	the node returned in N had no Parent. The caller continued
	processing of this orphaned node. In some cases that caused a
	crash (e.g. Remove_Side_Effects climbs up Parents in a loop,
	and trips over the Empty Parent). The solution is to make N an
	'in' parameter.  Instead of rewriting it, return the list of
	post-call actions, so the caller can do the rewriting later,
	after N has been fully processed.
	(Expand_Call_Helper): Move most of Expand_Call here. It has
	too many premature 'return' statements, and we want to do the
	rewriting on return.
	(Insert_Post_Call_Actions): New procedure to insert the post-call
	actions in the appropriate place. In the problematic case,
	that involves rewriting N as an Expression_With_Actions.
	(Expand_Call): Call the new procedures Expand_Call_Helper and
	Insert_Post_Call_Actions.

From-SVN: r247178
parent 36357cf3
Showing with 69 additions and 7 deletions
gcc/ada/ChangeLog
2017-04-25 Bob Duff <duff@adacore.com>
* sem_prag.adb (No_Return): Give an error if the pragma applies
to a body. Specialize the error for the specless body case,
as is done for (e.g.) pragma Convention.
* debug.adb: Add switch -gnatd.J to disable the above legality
checks. This is mainly for use in our test suite, to avoid
rewriting a lot of illegal (but working) code. It might also
be useful to customers. Under this switch, if a pragma No_Return
applies to a body, and the procedure raises an exception (as it
should), the pragma has no effect. If the procedure does return,
execution is erroneous.
2017-04-25 Bob Duff <duff@adacore.com>
* exp_ch6.adb (Expand_Actuals): This is the
root of the problem. It took N as an 'in out' parameter, and in
some cases, rewrote N, but then set N to Original_Node(N). So
the node returned in N had no Parent. The caller continued
processing of this orphaned node. In some cases that caused a
crash (e.g. Remove_Side_Effects climbs up Parents in a loop,
and trips over the Empty Parent). The solution is to make N an
'in' parameter. Instead of rewriting it, return the list of
post-call actions, so the caller can do the rewriting later,
after N has been fully processed.
(Expand_Call_Helper): Move most of Expand_Call here. It has
too many premature 'return' statements, and we want to do the
rewriting on return.
(Insert_Post_Call_Actions): New procedure to insert the post-call
actions in the appropriate place. In the problematic case,
that involves rewriting N as an Expression_With_Actions.
(Expand_Call): Call the new procedures Expand_Call_Helper and
Insert_Post_Call_Actions.
2017-04-25 Ed Schonberg <schonberg@adacore.com>
* sem_prag.adb (Inherits_Class_Wide_Pre): Cleanup code, handle
......
gcc/ada/debug.adb
......@@ -127,7 +127,7 @@ package body Debug is
-- d.G Ignore calls through generic formal parameters for elaboration
-- d.H GNSA mode for ASIS
-- d.I Do not ignore enum representation clauses in CodePeer mode
-- d.J
-- d.J Relaxed rules for pragma No_Return
-- d.K Enable generation of contract-only procedures in CodePeer mode
-- d.L Depend on back end for limited types in if and case expressions
-- d.M Relaxed RM semantics
......@@ -645,6 +645,11 @@ package body Debug is
-- cases being able to change this default might be useful to remove
-- some false positives.
-- d.J Relaxed rules for pragma No_Return. A pragma No_Return is illegal
-- if it applies to a body. This switch disables the legality check
-- for that. If the procedure does in fact return normally, execution
-- is erroneous, and therefore unpredictable.
-- d.K Enable generation of contract-only procedures in CodePeer mode and
-- report a warning on subprograms for which the contract-only body
-- cannot be built. Currently reported on subprograms defined in
......
gcc/ada/sem_prag.adb
......@@ -7621,7 +7621,7 @@ package body Sem_Prag is
end if;
-- Check that we are not applying this to a specless body. Relax this
-- check if Relaxed_RM_Semantics to accomodate other Ada compilers.
-- check if Relaxed_RM_Semantics to accommodate other Ada compilers.
if Is_Subprogram (E)
and then Nkind (Parent (Declaration_Node (E))) = N_Subprogram_Body
......@@ -8084,8 +8084,8 @@ package body Sem_Prag is
N_Subprogram_Body
then
Error_Pragma
("pragma% requires separate spec"
& " and must come before body");
("pragma% requires separate spec" &
" and must come before body");
end if;
-- Test result type if given, note that the result type
......@@ -18177,6 +18177,29 @@ package body Sem_Prag is
and then Scope (E) = Current_Scope
loop
if Ekind_In (E, E_Procedure, E_Generic_Procedure) then
-- Check that the pragma is not applied to a body.
-- First check the specless body case, to give a
-- different error message. These checks do not apply
-- if Relaxed_RM_Semantics, to accommodate other Ada
-- compilers. Disable these checks under -gnatd.J.
if not Debug_Flag_Dot_JJ then
if Nkind (Parent (Declaration_Node (E))) =
N_Subprogram_Body
and then not Relaxed_RM_Semantics
then
Error_Pragma
("pragma% requires separate spec" &
" and must come before body");
end if;
-- Now the "specful" body case
if Rep_Item_Too_Late (E, N) then
raise Pragma_Exit;
end if;
end if;
Set_No_Return (E);
-- A pragma that applies to a Ghost entity becomes Ghost
......@@ -26125,7 +26148,7 @@ package body Sem_Prag is
raise Program_Error;
end if;
-- To accomodate partial decoration of disabled SPARK features, this
-- To accommodate partial decoration of disabled SPARK features, this
-- routine may be called with illegal input. If this is the case, do
-- not raise Program_Error.
......@@ -28031,7 +28054,7 @@ package body Sem_Prag is
(Item => First (Choices (Clause)),
Is_Input => False);
-- To accomodate partial decoration of disabled SPARK features, this
-- To accommodate partial decoration of disabled SPARK features, this
-- routine may be called with illegal input. If this is the case, do
-- not raise Program_Error.
......@@ -28105,7 +28128,7 @@ package body Sem_Prag is
end loop;
end if;
-- To accomodate partial decoration of disabled SPARK features, this
-- To accommodate partial decoration of disabled SPARK features, this
-- routine may be called with illegal input. If this is the case, do
-- not raise Program_Error.
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment