From: Piotr Trojanek <troja...@adacore.com> GNAT has a heuristic to warn about missing return statements in functions. This warning was escalated to errors when operating in GNATprove mode and SPARK_Mode was On. However, this heuristic was imprecise and caused spurious errors. Also, it was applied after the Push_Scope/End_Scope, so for functions acting as compilation units it was using the wrong SPARK_Mode.
It is better to simply leave this detection to GNATprove. gcc/ada/ * sem_ch6.adb (Check_Statement_Sequence): Only warn about missing return statements and let GNATprove emit a check when needed. Tested on x86_64-pc-linux-gnu, committed on master. --- gcc/ada/sem_ch6.adb | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-) diff --git a/gcc/ada/sem_ch6.adb b/gcc/ada/sem_ch6.adb index 62ca985bf87..4e64833b3f7 100644 --- a/gcc/ada/sem_ch6.adb +++ b/gcc/ada/sem_ch6.adb @@ -7315,18 +7315,11 @@ package body Sem_Ch6 is -- already, so the Assert_False is for the assertions off case. if not Raise_Exception_Call and then not Assert_False then - - -- In GNATprove mode, it is an error to have a missing return - - Error_Msg_Warn := SPARK_Mode /= On; - - -- Issue error message or warning - Error_Msg_N - ("RETURN statement missing following this statement<<!", + ("RETURN statement missing following this statement??!", Last_Stm); Error_Msg_N - ("\Program_Error [<<!", Last_Stm); + ("\Program_Error [??!", Last_Stm); end if; -- Note: we set Err even though we have not issued a warning -- 2.40.0