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From: Pierre-Marie de Rodat <derodat@adacore.com>
To: gcc-patches@gcc.gnu.org
Cc: Bob Duff <duff@adacore.com>
Subject: [Ada] Prevent crash in Is_Reachable
Date: Mon, 12 Aug 2019 09:46:00 -0000	[thread overview]
Message-ID: <20190812090251.GA22670@adacore.com> (raw)

[-- Attachment #1: Type: text/plain, Size: 354 bytes --]

This patch fixes a bug in Is_Reachable, which causes a crash when checks
are on.

Tested on x86_64-pc-linux-gnu, committed on trunk

2019-08-12  Bob Duff  <duff@adacore.com>

gcc/ada/

	* libgnat/a-cbmutr.adb (Is_Reachable): Declare Idx to be of the
	base subtype.  Clearly it makes no sense to loop "while Idx >=
	0", if Idx is of a nonnegative subtype.

[-- Attachment #2: patch.diff --]
[-- Type: text/x-diff, Size: 397 bytes --]

--- gcc/ada/libgnat/a-cbmutr.adb
+++ gcc/ada/libgnat/a-cbmutr.adb
@@ -1767,10 +1767,8 @@ package body Ada.Containers.Bounded_Multiway_Trees is
      (Container : Tree;
       From, To  : Count_Type) return Boolean
    is
-      Idx : Count_Type;
-
+      Idx : Count_Type'Base := From;
    begin
-      Idx := From;
       while Idx >= 0 loop
          if Idx = To then
             return True;


                 reply	other threads:[~2019-08-12  9:10 UTC|newest]

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