#ifndef _NTSXS_H
// begin_private

/**
 * Per-thread runtime activation-context stack: 40 bytes on x64 and 24 bytes on x86.
 * ActiveFrame is the top of the stack; FrameListCache contains cached frame allocations.
 * Flags bit 0 disables queries. Bit 1 marks inline storage, which is not freed as a heap block
 * by RtlFreeActivationContextStack (for example, the stack embedded in the TEB).
 */
typedef struct _ACTIVATION_CONTEXT_STACK
{
    PRTL_ACTIVATION_CONTEXT_STACK_FRAME ActiveFrame;
    LIST_ENTRY FrameListCache;
    ULONG Flags; // ACTIVATION_CONTEXT_STACK_FLAG_*
    ULONG NextCookieSequenceNumber;
    ULONG StackId;
} ACTIVATION_CONTEXT_STACK, *PACTIVATION_CONTEXT_STACK;

// end_private
#endif
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