std.debug: fix FP unwind progress check for stackGrowth() == .up targets

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Alex Rønne Petersen 2025-10-20 03:44:51 +02:00
parent a689c38197
commit c13355abda
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@ -974,11 +974,15 @@ const StackIterator = union(enum) {
const ra_ptr: *const usize = @ptrFromInt(ra_addr);
const bp = applyOffset(bp_ptr.*, stack_bias) orelse return .end;
// The stack grows downards, so `bp > fp` should always hold. If it doesn't, this
// frame is invalid, so we'll treat it as though it we reached end of stack. The
// If the stack grows downwards, `bp > fp` should always hold; conversely, if it
// grows upwards, `bp < fp` should always hold. If that is not the case, this
// frame is invalid, so we'll treat it as though we reached end of stack. The
// exception is address 0, which is a graceful end-of-stack signal, in which case
// *this* return address is valid and the *next* iteration will be the last.
if (bp != 0 and bp <= fp) return .end;
if (bp != 0 and switch (comptime builtin.target.stackGrowth()) {
.down => bp <= fp,
.up => bp >= fp,
}) return .end;
it.fp = bp;
const ra = stripInstructionPtrAuthCode(ra_ptr.*);