text: #ifndef COSMOPOLITAN_LIBC_LOG_BACKTRACE_H_
  #define COSMOPOLITAN_LIBC_LOG_BACKTRACE_H_
  #include "libc/nexgen32e/stackframe.h"
  #include "libc/runtime/memtrack.internal.h"
  #include "libc/runtime/symbols.internal.h"
  #if !(__ASSEMBLER__ + __LINKER__ + 0)
  COSMOPOLITAN_C_START_
  
  forceinline pureconst bool IsValidStackFramePointer(struct StackFrame *x) {
    return IsLegalPointer(x) && !((uintptr_t)x & 15) &&
           (IsStaticStackFrame((uintptr_t)x >> 16) ||
            IsSigAltStackFrame((uintptr_t)x >> 16) ||
            IsOldStackFrame((uintptr_t)x >> 16));
  }
  
  void ShowBacktrace(int, const struct StackFrame *);
  int PrintBacktraceUsingSymbols(int, const struct StackFrame *,
                                 struct SymbolTable *);
  
  COSMOPOLITAN_C_END_
  #endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
  #endif /* COSMOPOLITAN_LIBC_LOG_BACKTRACE_H_ */
  