From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1914) id F39093858010; Mon, 25 Oct 2021 15:08:25 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org F39093858010 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Pierre-Marie de Rodat To: gcc-cvs@gcc.gnu.org Subject: [gcc r12-4674] [Ada] Reference in Unbounded_String is almost never null X-Act-Checkin: gcc X-Git-Author: Piotr Trojanek X-Git-Refname: refs/heads/master X-Git-Oldrev: f977a792721cdaa0d6cbda689b3a6930cf510f7e X-Git-Newrev: 98f939e9c98403636f10168be568bb9b800aac41 Message-Id: <20211025150825.F39093858010@sourceware.org> Date: Mon, 25 Oct 2021 15:08:25 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 25 Oct 2021 15:08:26 -0000 https://gcc.gnu.org/g:98f939e9c98403636f10168be568bb9b800aac41 commit r12-4674-g98f939e9c98403636f10168be568bb9b800aac41 Author: Piotr Trojanek Date: Tue Jun 15 23:32:51 2021 +0200 [Ada] Reference in Unbounded_String is almost never null gcc/ada/ * libgnat/a-strunb.ads (Unbounded_String): Reference is never null. * libgnat/a-strunb.adb (Finalize): Copy reference while it needs to be deallocated. Diff: --- gcc/ada/libgnat/a-strunb.adb | 10 ++++++++-- gcc/ada/libgnat/a-strunb.ads | 4 ++-- 2 files changed, 10 insertions(+), 4 deletions(-) diff --git a/gcc/ada/libgnat/a-strunb.adb b/gcc/ada/libgnat/a-strunb.adb index 4727f965486..0d62e4b379f 100644 --- a/gcc/ada/libgnat/a-strunb.adb +++ b/gcc/ada/libgnat/a-strunb.adb @@ -505,8 +505,14 @@ package body Ada.Strings.Unbounded is -- Note: Don't try to free statically allocated null string if Object.Reference /= Null_String'Access then - Deallocate (Object.Reference); - Object.Reference := Null_Unbounded_String.Reference; + declare + Reference_Copy : String_Access := Object.Reference; + -- The original reference cannot be null, so we must create a + -- copy which will become null when deallocated. + begin + Deallocate (Reference_Copy); + Object.Reference := Null_Unbounded_String.Reference; + end; Object.Last := 0; end if; end Finalize; diff --git a/gcc/ada/libgnat/a-strunb.ads b/gcc/ada/libgnat/a-strunb.ads index b3050fdb5a3..2f5bd948f3b 100644 --- a/gcc/ada/libgnat/a-strunb.ads +++ b/gcc/ada/libgnat/a-strunb.ads @@ -746,8 +746,8 @@ private renames To_Unbounded_String; type Unbounded_String is new AF.Controlled with record - Reference : String_Access := Null_String'Access; - Last : Natural := 0; + Reference : not null String_Access := Null_String'Access; + Last : Natural := 0; end record with Put_Image => Put_Image; procedure Put_Image