The public symbol file NTKRNLMP.PDB for the original release of 64-bit Windows 10 says nothing of any header named AMD64.H, yet one certainly does exist and surely is included when compiling the kernel’s source code—just not when compiling the separate source file that exists only for merging type information into the public symbol file.

Type information from including AMD64.H does not appear in any of the symbol files from the downloadable package of public symbols for the original Windows 10. It is known, however, from a statically linked library named CLFSMGMT.LIB which Microsoft publishes with the Software Development Kit (SDK) for Windows 10. This library archives an object file that was produced from creating a pre-compiled header. it plausibly is complete because much of the point to building a pre-compiled header is that it carries the definitions of all types that might be used in any other compilation (with the same options and macro definitions). It tells of an AMD64.H header at


Types and line numbers that are disclosed by this library are tablulated below. Curiously, there is only the one:

Line Number Type
528 struct _KDPC_STACK_FRAME

The header AMD64.H is not known in any Device Driver Kit (DDK) or Windows Driver Kit (WDK). Whether the one type it defines is important outside the kernel is debatable—so too is whether it’s important for an understanding even within the kernel—but it must count among the most obscure in all writing that has yet been published about the Windows kernel from outside Microsoft: today, 6th February 2023, Google finds exactly zero matches for it.