From patchwork Wed May 5 08:20:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pierre-Marie de Rodat X-Patchwork-Id: 1474159 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gcc.gnu.org (client-ip=8.43.85.97; helo=sourceware.org; envelope-from=gcc-patches-bounces@gcc.gnu.org; receiver=) Received: from sourceware.org (ip-8-43-85-97.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4FZqR44hYrz9sRR for ; Wed, 5 May 2021 18:20:48 +1000 (AEST) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id CEA3539A401A; Wed, 5 May 2021 08:20:16 +0000 (GMT) X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from rock.gnat.com (rock.gnat.com [205.232.38.15]) by sourceware.org (Postfix) with ESMTP id B2ECF3988884 for ; Wed, 5 May 2021 08:20:07 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org B2ECF3988884 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=adacore.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=derodat@adacore.com Received: from localhost (localhost.localdomain [127.0.0.1]) by filtered-rock.gnat.com (Postfix) with ESMTP id 4BFE3561E5; Wed, 5 May 2021 04:20:05 -0400 (EDT) X-Virus-Scanned: Debian amavisd-new at gnat.com Received: from rock.gnat.com ([127.0.0.1]) by localhost (rock.gnat.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id uHxrUiO8fjSg; Wed, 5 May 2021 04:20:05 -0400 (EDT) Received: from tron.gnat.com (tron.gnat.com [IPv6:2620:20:4000:0:46a8:42ff:fe0e:e294]) by rock.gnat.com (Postfix) with ESMTP id 252C91174DE; Wed, 5 May 2021 04:20:05 -0400 (EDT) Received: by tron.gnat.com (Postfix, from userid 4862) id 24762103; Wed, 5 May 2021 04:20:05 -0400 (EDT) Date: Wed, 5 May 2021 04:20:05 -0400 From: Pierre-Marie de Rodat To: gcc-patches@gcc.gnu.org Subject: [Ada] Handle defaults in declare_expressions in postconditions Message-ID: <20210505082005.GA31251@adacore.com> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) X-Spam-Status: No, score=-12.4 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Ed Schonberg Errors-To: gcc-patches-bounces@gcc.gnu.org Sender: "Gcc-patches" In Ada2020 the expression for a postcondition can be a Declare_Expression containing object declarations with defaults. These defaults may generate local subtypes, but as for other default expressions their full expansion must be deferred, typically to the freeze point of the object being declared, which for a postcondition will be the analysis of the generated postcondition procedure. Nevertheless the declarations for such subtypes must appear in the tree to complete the semantic analysis of the default expression itself. Given that Insert_Actions is disabled when In_Spec_Expression is set, we place the generated declaration directly ahead of the local declaration, and provide the needed semantic information for the subtype. Tested on x86_64-pc-linux-gnu, committed on trunk gcc/ada/ * sem_ch3.adb (Find_Type_Of_Object): When In_Spec_Expression is set and the object declaration generates a subtype indication, build the corresponding subtype declaration and place it in tree without the use of Insert_Actions, which is disabled in this context. diff --git a/gcc/ada/sem_ch3.adb b/gcc/ada/sem_ch3.adb --- a/gcc/ada/sem_ch3.adb +++ b/gcc/ada/sem_ch3.adb @@ -17827,6 +17827,44 @@ package body Sem_Ch3 is T := Make_Defining_Identifier (Sloc (P), Nam); + -- If In_Spec_Expression, for example within a pre/postcondition, + -- provide enough information for use of the subtype without + -- depending on full analysis and freezing, which will happen when + -- building the correspondiing subprogram. + + if In_Spec_Expression then + Analyze (Subtype_Mark (Obj_Def)); + + declare + Base_T : constant Entity_Id := Entity (Subtype_Mark (Obj_Def)); + Decl : constant Node_Id := + Make_Subtype_Declaration (Sloc (P), + Defining_Identifier => T, + Subtype_Indication => Relocate_Node (Obj_Def)); + begin + Set_Etype (T, Base_T); + Set_Ekind (T, Subtype_Kind (Ekind (Base_T))); + Set_Parent (T, Obj_Def); + + if Ekind (T) = E_Array_Subtype then + Set_First_Index (T, First_Index (Base_T)); + Set_Is_Constrained (T); + + elsif Ekind (T) = E_Record_Subtype then + Set_First_Entity (T, First_Entity (Base_T)); + Set_Has_Discriminants (T, Has_Discriminants (Base_T)); + Set_Is_Constrained (T); + end if; + + Insert_Before (Related_Nod, Decl); + end; + + return T; + end if; + + -- When generating code, insert subtype declaration ahead of + -- declaration that generated it. + Insert_Action (Obj_Def, Make_Subtype_Declaration (Sloc (P), Defining_Identifier => T,