From: Robert Dewar Date: Wed, 26 Mar 2008 07:42:37 +0000 (+0100) Subject: sem_res.adb (Check_Infinite_Recursion): Diagnose definite infinite recursion and... X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=26570b21745ef73ffb6df68712cd3fb6932fe602;p=gcc.git sem_res.adb (Check_Infinite_Recursion): Diagnose definite infinite recursion and raise SE directly. 2008-03-26 Robert Dewar * sem_res.adb (Check_Infinite_Recursion): Diagnose definite infinite recursion and raise SE directly. (Resolve_Actuals): Reset Never_Set_In_Source if warnings off is set for formal type for IN mode parameter. From-SVN: r133579 --- diff --git a/gcc/ada/sem_res.adb b/gcc/ada/sem_res.adb index a741c467648..9e8687daad6 100644 --- a/gcc/ada/sem_res.adb +++ b/gcc/ada/sem_res.adb @@ -6,7 +6,7 @@ -- -- -- B o d y -- -- -- --- Copyright (C) 1992-2007, Free Software Foundation, Inc. -- +-- Copyright (C) 1992-2008, Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- @@ -720,8 +720,34 @@ package body Sem_Res is -- Start of processing for Check_Infinite_Recursion begin - -- Loop moving up tree, quitting if something tells us we are - -- definitely not in an infinite recursion situation. + -- Special case, if this is a procedure call and is a call to the + -- current procedure with the same argument list, then this is for + -- sure an infinite recursion and we insert a call to raise SE. + + if Is_List_Member (N) + and then List_Length (List_Containing (N)) = 1 + and then Same_Argument_List + then + declare + P : constant Node_Id := Parent (N); + begin + if Nkind (P) = N_Handled_Sequence_Of_Statements + and then Nkind (Parent (P)) = N_Subprogram_Body + and then Is_Empty_List (Declarations (Parent (P))) + then + Error_Msg_N ("!?infinite recursion", N); + Error_Msg_N ("\!?Storage_Error will be raised at run time", N); + Insert_Action (N, + Make_Raise_Storage_Error (Sloc (N), + Reason => SE_Infinite_Recursion)); + return True; + end if; + end; + end if; + + -- If not that special case, search up tree, quitting if we reach a + -- construct (e.g. a conditional) that tells us that this is not a + -- case for an infinite recursion warning. C := N; loop @@ -738,10 +764,10 @@ package body Sem_Res is elsif Nkind (P) = N_Handled_Sequence_Of_Statements and then C /= First (Statements (P)) then - -- If the call is the expression of a return statement and - -- the actuals are identical to the formals, it's worth a - -- warning. However, we skip this if there is an immediately - -- preceding raise statement, since the call is never executed. + -- If the call is the expression of a return statement and the + -- actuals are identical to the formals, it's worth a warning. + -- However, we skip this if there is an immediately preceding + -- raise statement, since the call is never executed. -- Furthermore, this corresponds to a common idiom: @@ -3045,6 +3071,21 @@ package body Sem_Res is A_Typ := Etype (A); F_Typ := Etype (F); + -- For mode IN, if actual is an entity, and the type of the formal + -- has warnings suppressed, then we reset Never_Set_In_Source for + -- the calling entity. The reason for this is to catch cases like + -- GNAT.Spitbol.Patterns.Vstring_Var where the called subprogram + -- uses trickery to modify an IN parameter. + + if Ekind (F) = E_In_Parameter + and then Is_Entity_Name (A) + and then Present (Entity (A)) + and then Ekind (Entity (A)) = E_Variable + and then Has_Warnings_Off (F_Typ) + then + Set_Never_Set_In_Source (Entity (A), False); + end if; + -- Perform error checks for IN and IN OUT parameters if Ekind (F) /= E_Out_Parameter then @@ -4625,17 +4666,23 @@ package body Sem_Res is if Comes_From_Source (N) then Scop := Current_Scope; + -- Issue warning for possible infinite recursion in the absence + -- of the No_Recursion restriction. + if Nam = Scop and then not Restriction_Active (No_Recursion) and then Check_Infinite_Recursion (N) then -- Here we detected and flagged an infinite recursion, so we do - -- not need to test the case below for further warnings. + -- not need to test the case below for further warnings. Also if + -- we now have a raise SE node, we are all done. - null; + if Nkind (N) = N_Raise_Storage_Error then + return; + end if; - -- If call is to immediately containing subprogram, then check for - -- the case of a possible run-time detectable infinite recursion. + -- If call is to immediately containing subprogram, then check for + -- the case of a possible run-time detectable infinite recursion. else Scope_Loop : while Scop /= Standard_Standard loop @@ -4761,7 +4808,7 @@ package body Sem_Res is if Is_Inlined (Nam) and then Present (First_Rep_Item (Nam)) and then Nkind (First_Rep_Item (Nam)) = N_Pragma - and then Chars (First_Rep_Item (Nam)) = Name_Inline_Always + and then Pragma_Name (First_Rep_Item (Nam)) = Name_Inline_Always then null; @@ -7196,7 +7243,7 @@ package body Sem_Res is Orig : constant Node_Id := Original_Node (Parent (N)); begin if Nkind (Orig) = N_Pragma - and then Chars (Orig) = Name_Assert + and then Pragma_Name (Orig) = Name_Assert then -- Don't want to warn if original condition is explicit False