From 44f83ca4f452061f7e8c7c4dabd5235af1295a8a Mon Sep 17 00:00:00 2001 From: Justin Squirek Date: Wed, 3 Jul 2019 08:13:51 +0000 Subject: [PATCH] [Ada] Missing consistency check for constant modifier This patch fixes an issue whereby instantiations of generic packages were incorrectly allowed despite formal and actual subprograms not having matching declarations with anonymous constant access type parameters. ------------ -- Source -- ------------ -- gen1.ads package Gen1 is generic with procedure View (IA : not null access constant Integer); procedure Dispatch (IA : access Integer); end; -- gen2.adb package body Gen1 is procedure Dispatch (IA : access Integer) is begin View (IA); end; end; -- bad1.ads with Gen1; package Bad1 is procedure Bad_View (IA : not null access Integer); procedure Bad_Dispatch is new Gen1.Dispatch (Bad_View); end; -- bad1.adb package body Bad1 is procedure Bad_View (IA : not null access Integer) is begin IA.all := IA.all + 1; end; end; -- gen2.ads package Gen2 is generic with procedure View (IA : access constant Integer); procedure Dispatch (IA : access Integer); end; -- gen2.adb package body Gen2 is procedure Dispatch (IA : access Integer) is begin View (IA); end; end; -- bad2.ads with Gen2; package Bad2 is procedure Bad_View (IA : access Integer); procedure Bad_Dispatch is new Gen2.Dispatch (Bad_View); end; -- bad2.adb package body Bad2 is procedure Bad_View (IA : access Integer) is begin IA.all := IA.all + 1; end; end; ----------------- -- Compilation -- ----------------- $ gnatmake -q bad1.adb $ bad1.ads:4:04: instantiation error at gen1.ads:3 $ bad1.ads:4:04: not mode conformant with declaration at line 3 $ bad1.ads:4:04: constant modifier does not match $ gnatmake: "bad1.adb" compilation error $ gnatmake -q bad2.adb $ bad2.ads:4:04: instantiation error at gen2.ads:3 $ bad2.ads:4:04: not mode conformant with declaration at line 3 $ bad2.ads:4:04: constant modifier does not match $ gnatmake: "bad2.adb" compilation error 2019-07-03 Justin Squirek gcc/ada/ * sem_ch6.adb (Check_Conformance): Add expression checking for constant modifiers in anonymous access types (in addition to "non-null" types) so that they are considered "matching" for subsequent conformance tests. From-SVN: r272963 --- gcc/ada/ChangeLog | 7 +++++++ gcc/ada/sem_ch6.adb | 8 ++++++-- 2 files changed, 13 insertions(+), 2 deletions(-) diff --git a/gcc/ada/ChangeLog b/gcc/ada/ChangeLog index ada9c2b..879b776 100644 --- a/gcc/ada/ChangeLog +++ b/gcc/ada/ChangeLog @@ -1,3 +1,10 @@ +2019-07-03 Justin Squirek + + * sem_ch6.adb (Check_Conformance): Add expression checking for + constant modifiers in anonymous access types (in addition to + "non-null" types) so that they are considered "matching" for + subsequent conformance tests. + 2019-07-03 Arnaud Charlet * doc/gnat_rm/standard_and_implementation_defined_restrictions.rst: diff --git a/gcc/ada/sem_ch6.adb b/gcc/ada/sem_ch6.adb index d635543c..cf1b0e7 100644 --- a/gcc/ada/sem_ch6.adb +++ b/gcc/ada/sem_ch6.adb @@ -5444,10 +5444,14 @@ package body Sem_Ch6 is and then Directly_Designated_Type (Old_Formal_Base) = Directly_Designated_Type (New_Formal_Base) and then ((Is_Itype (Old_Formal_Base) - and then Can_Never_Be_Null (Old_Formal_Base)) + and then (Can_Never_Be_Null (Old_Formal_Base) + or else Is_Access_Constant + (Old_Formal_Base))) or else (Is_Itype (New_Formal_Base) - and then Can_Never_Be_Null (New_Formal_Base))); + and then (Can_Never_Be_Null (New_Formal_Base) + or else Is_Access_Constant + (New_Formal_Base)))); -- Types must always match. In the visible part of an instance, -- usual overloading rules for dispatching operations apply, and -- 2.7.4