[Ada] Compiler hangs on evaluation of use-clause within package context
Pierre-Marie de Rodat
derodat@adacore.com
Fri Sep 29 13:24:00 GMT 2017
Due to the installation order of packages within a context clause it is
possible to create circularities within the Prev_Use_Clause clain. This patch
corrects this issue by identifying this case through the use of an extra check.
Tested on x86_64-pc-linux-gnu, committed on trunk
2017-09-29 Justin Squirek <squirek@adacore.com>
* sem_ch8.adb (Analyze_Use_Package): Add sanity check to avoid
circularities in the use-clause chain.
-------------- next part --------------
Index: sem_ch8.adb
===================================================================
--- sem_ch8.adb (revision 253285)
+++ sem_ch8.adb (working copy)
@@ -3782,9 +3782,10 @@
-- before setting its previous use clause.
if Ekind (Pack) = E_Package
- and then Present (Current_Use_Clause (Pack))
- and then Current_Use_Clause (Pack) /= N
- and then No (Prev_Use_Clause (N))
+ and then Present (Current_Use_Clause (Pack))
+ and then Current_Use_Clause (Pack) /= N
+ and then No (Prev_Use_Clause (N))
+ and then Prev_Use_Clause (Current_Use_Clause (Pack)) /= N
then
Set_Prev_Use_Clause (N, Current_Use_Clause (Pack));
end if;
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