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| author | Bob Duff <duff@adacore.com> | 2021-11-30 16:00:40 -0500 |
|---|---|---|
| committer | Pierre-Marie de Rodat <derodat@adacore.com> | 2022-01-05 11:32:35 +0000 |
| commit | a6505936a35e7a5c66e36f7c4e2032c5c7f64838 (patch) | |
| tree | 161f8a7cce508871ac49e9bcbec33d9ece175b79 /gcc | |
| parent | 54403a8130c126cc3e901341dac64afbc7273347 (diff) | |
| download | gcc-a6505936a35e7a5c66e36f7c4e2032c5c7f64838.zip gcc-a6505936a35e7a5c66e36f7c4e2032c5c7f64838.tar.gz gcc-a6505936a35e7a5c66e36f7c4e2032c5c7f64838.tar.bz2 | |
[Ada] Prevent Get_Current_Value_Condition from returning the same node
gcc/ada/
* exp_util.ads (Get_Current_Value_Condition): Belt: Add a
postcondition that Val /= Var.
* sem_util.adb (Known_Null): Suspenders: Raise Program_Error if
Get_Current_Value_Condition returned the same value. This will
be enabled even without assertions, because infinite recursion
is a nuisance -- better to crash if this bug ever occurs.
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ada/exp_util.ads | 2 | ||||
| -rw-r--r-- | gcc/ada/sem_util.adb | 7 |
2 files changed, 8 insertions, 1 deletions
diff --git a/gcc/ada/exp_util.ads b/gcc/ada/exp_util.ads index 2b61132..773fa01 100644 --- a/gcc/ada/exp_util.ads +++ b/gcc/ada/exp_util.ads @@ -703,7 +703,7 @@ package Exp_Util is procedure Get_Current_Value_Condition (Var : Node_Id; Op : out Node_Kind; - Val : out Node_Id); + Val : out Node_Id) with Post => Val /= Var; -- This routine processes the Current_Value field of the variable Var. If -- the Current_Value field is null or if it represents a known value, then -- on return Cond is set to N_Empty, and Val is set to Empty. diff --git a/gcc/ada/sem_util.adb b/gcc/ada/sem_util.adb index 49a58e3c..7064dfa 100644 --- a/gcc/ada/sem_util.adb +++ b/gcc/ada/sem_util.adb @@ -22062,6 +22062,13 @@ package body Sem_Util is Get_Current_Value_Condition (N, Op, Val); + -- If Get_Current_Value_Condition were to return Val = N, then the + -- recursion below could be infinite. + + if Val = N then + raise Program_Error; + end if; + if Known_Null (Val) then if Op = N_Op_Eq then return True; |