On PPC, Darwin uses the same code as other parts of the port, I suspect that the False was a historical relic.
(perhaps I could have applied this with my Darwin maintainer’s hat, or as obvious, but wasn’t sure for the Ada sub-tree) OK for trunk? Thanks Iain 2019-07-01 Iain Sandoe <i...@sandoe.co.uk> * libgnat/system-darwin-ppc.ads: Set Stack_Check_Probes True for PPC Darwin. diff --git a/gcc/ada/libgnat/system-darwin-ppc.ads b/gcc/ada/libgnat/system-darwin-ppc.ads index d314b66..9adc2de 100644 --- a/gcc/ada/libgnat/system-darwin-ppc.ads +++ b/gcc/ada/libgnat/system-darwin-ppc.ads @@ -158,7 +158,7 @@ private Preallocated_Stacks : constant Boolean := False; Signed_Zeros : constant Boolean := True; Stack_Check_Default : constant Boolean := False; - Stack_Check_Probes : constant Boolean := False; + Stack_Check_Probes : constant Boolean := True; Stack_Check_Limits : constant Boolean := False; Support_Aggregates : constant Boolean := True; Support_Atomic_Primitives : constant Boolean := Word_Size = 64;