From 15871a53a98ad58df7560490408d0942c6ffbdb9 Mon Sep 17 00:00:00 2001
From: Valentin Perrelle <valentin.perrelle@cea.fr>
Date: Mon, 18 Mar 2019 17:53:06 +0100
Subject: [PATCH] [Variadic] Distinguish various cast types
---
src/plugins/variadic/standard.ml | 61 ++++++++++++++++++--------------
1 file changed, 35 insertions(+), 26 deletions(-)
diff --git a/src/plugins/variadic/standard.ml b/src/plugins/variadic/standard.ml
index 8f2aac621af..d5b98d5d1d1 100644
--- a/src/plugins/variadic/standard.ml
+++ b/src/plugins/variadic/standard.ml
@@ -78,24 +78,29 @@ let integral_rep ikind =
let expose t =
Cil.type_remove_attributes_for_c_cast (Cil.unrollType t)
-let is_equivalent_enum given expected =
- match expose given, expose expected with
- | TInt (i1,a1), TEnum({ekind=i2},a2)
- | TEnum({ekind=i1},a1), TInt (i2,a2) ->
- integral_rep i1 = integral_rep i2 &&
- Cil_datatype.Attributes.equal a1 a2
- | _, _ -> false
+(* From most permissive to least permissive *)
+type castability = Strict (* strictly allowed by the C standard *)
+ | Tolerated (* tolerated in practice *)
+ | NonPortable (* non-portable minor deviation *)
+ | NonStrict (* only allowed in non-strict mode *)
+ | Never (* never allowed *)
let can_cast given expected =
match expose given, expose expected with
+ | t1, t2 when Cil_datatype.Typ.equal t1 t2 -> Strict
| (TInt (i1,a1) | TEnum({ekind=i1},a1)),
- (TInt (i2,a2) | TEnum({ekind=i2},a2))
- when not (Strict.get ()) || is_extended_integer_type given ->
- integral_rep i1 = integral_rep i2 &&
- Cil_datatype.Attributes.equal a1 a2
- | TPtr _, TPtr _ -> true
- | exposed_given, exposed_expected ->
- Cil_datatype.Typ.equal exposed_given exposed_expected
+ (TInt (i2,a2) | TEnum({ekind=i2},a2)) ->
+ if integral_rep i1 <> integral_rep i2 ||
+ not (Cil_datatype.Attributes.equal a1 a2) then
+ Never
+ else if is_extended_integer_type given then
+ Tolerated
+ else if i1 = i2 then
+ NonPortable
+ else
+ NonStrict
+ | TPtr _, TPtr _ -> Strict
+ | _, _ -> Never
let does_fit exp typ =
match Cil.constFoldToInt exp, Cil.unrollType typ with
@@ -114,18 +119,22 @@ let pretty_typ fmt t =
(* cast the i-th argument exp to paramtyp *)
let cast_arg i paramtyp exp =
let argtyp = Cil.typeOf exp in
- if not (can_cast argtyp paramtyp) && not (does_fit exp paramtyp) then
- if Strict.get () && is_equivalent_enum argtyp paramtyp then
- Self.warning ~current:true
- "Possible portability issues with enum type for argument %d \
- (use -variadic-no-strict to avoid this warning)."
- (i + 1)
- else
- Self.warning ~current:true
- "Incorrect type for argument %d. \
- The argument will be cast from %a to %a."
- (i + 1)
- pretty_typ argtyp pretty_typ paramtyp;
+ if not (does_fit exp paramtyp) then
+ begin match can_cast argtyp paramtyp with
+ | Strict | Tolerated -> ()
+ | (NonPortable | NonStrict) when not (Strict.get ()) -> ()
+ | NonPortable ->
+ Self.warning ~current:true
+ "Possible portability issues with enum type for argument %d \
+ (use -variadic-no-strict to avoid this warning)."
+ (i + 1)
+ | NonStrict | Never ->
+ Self.warning ~current:true
+ "Incorrect type for argument %d. \
+ The argument will be cast from %a to %a."
+ (i + 1)
+ pretty_typ argtyp pretty_typ paramtyp
+ end;
Cil.mkCast ~force:false ~e:exp ~newt:paramtyp
--
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