Enhance beam_validator to check proper nesting of try/catch and catch

Every catch or try/catch must use a lower Y register number than any
enclosing catch or try/catch. That will ensure that when the stack
is scanned when an exception occurs, the innermost try/catch tag is
found first.

1 files changed, 10 insertions, 2 deletions

diff --git a/lib/compiler/test/beam_validator_SUITE.erl b/lib/compiler/test/beam_validator_SUITE.erl
index 63a13281a8..b8fff7b100 100644
--- a/lib/compiler/test/beam_validator_SUITE.erl
+++ b/lib/compiler/test/beam_validator_SUITE.erl
@@ -33,7 +33,7 @@
 	 state_after_fault_in_catch/1,no_exception_in_catch/1,
 	 undef_label/1,illegal_instruction/1,failing_gc_guard_bif/1,
 	 map_field_lists/1,cover_bin_opt/1,
-	 val_dsetel/1,bad_tuples/1]).
+	 val_dsetel/1,bad_tuples/1,bad_try_catch_nesting/1]).
 
 -include_lib("common_test/include/ct.hrl").
 
@@ -62,7 +62,7 @@ groups() ->
        state_after_fault_in_catch,no_exception_in_catch,
        undef_label,illegal_instruction,failing_gc_guard_bif,
        map_field_lists,cover_bin_opt,val_dsetel,
-       bad_tuples]}].
+       bad_tuples,bad_try_catch_nesting]}].
 
 init_per_suite(Config) ->
     Config.
@@ -523,6 +523,14 @@ bad_tuples(Config) ->
 
     ok.
 
+bad_try_catch_nesting(Config) ->
+    Errors = do_val(bad_try_catch_nesting, Config),
+    [{{bad_try_catch_nesting,main,2},
+      {{'try',{y,2},{f,3}},
+       7,
+       {bad_try_catch_nesting,{y,2},[{{y,1},{trytag,[5]}}]}}}] = Errors,
+    ok.
+
 %%%-------------------------------------------------------------------------
 
 transform_remove(Remove, Module) ->