[TCLCORE] Issue report: tcl9.0b3 build fails on Windows/aarch64

[Jan M. <0x...@gm...>]

When trying to build tcl9.0b3 on Windows 10/aarch64.

Invoking ./configure and make fails after a while with this message
(many preceding lines omitted):

gcc -c -I"." -I"C:/Users/jnml/src/modernc.org/tk9.0/tcl9.0b3/generic"
-I"C:/Users/jnml/src/modernc.org/tk9.0/tcl9.0b3/libtommath"
-I"C:/Users/jnml/src/modernc.org/tk9.0/tcl9.0b3/compat/zlib"
-I"C:/Users/jnml/src/modernc.org/tk9.0/tcl9.0b3/win" -O2
-fomit-frame-pointer -DMP_FIXED_CUTOFFS -D__USE_MINGW_ANSI_STDIO=0
-Wall -Wextra -Wshadow -
Wundef -Wwrite-strings -Wpointer-arith -Wc++-compat
-fextended-identifiers  -DMP_PREC=4 -pipe -DHAVE_CPUID=1
-finput-charset=UTF-8 -DPACKAGE_NAME=\"tcl\" -DPACKAGE_TARNAME=\"tcl\"
-DPACKAGE_VERSION=\"9.0\" -DPACKAGE_STRING=\"tcl\ 9.0\"
-DPACKAGE_BUGREPORT=\"\" -DPACKAGE_URL=\"\"
-DTCL_CFGVAL_ENCODING=\"utf-8\" -DHAVE_STDIO_H=1 -DHAVE_STD
LIB_H=1 -DHAVE_STRING_H=1 -DHAVE_INTTYPES_H=1 -DHAVE_STDINT_H=1
-DHAVE_STRINGS_H=1 -DHAVE_SYS_STAT_H=1 -DHAVE_SYS_TYPES_H=1
-DHAVE_UNISTD_H=1 -DSTDC_HEADERS=1 -DMODULE_SCOPE=extern
-DHAVE_NO_SEH=1 -DHAVE_STDBOOL_H=1 -DHAVE_CAST_TO_UNION=1
-DTCL_WITH_EXTERNAL_TOMMATH=1 -DHAVE_ZLIB=1 -DHAVE_INTPTR_T=1
-DHAVE_UINTPTR_T=1 -DZIPFS_BUILD=1 -DH
AVE_INTRIN_H=1 -DHAVE_WSPIAPI_H=1 -DNDEBUG=1 -DTCL_CFG_OPTIMIZED=1
-DBUILD_tcl "tclWin32Dll.c" -o tclWin32Dll.o
tclWin32Dll.c:442:5: error: call to undeclared function '__cpuid'; ISO
C99 and later do not support implicit function declarations
[-Wimplicit-function-declaration]
  442 |     __cpuid((int *)regsPtr, index);
      |     ^
1 error generated.
make: *** [Makefile:758: tclWin32Dll.o] Error 1

jnml@pi64 CLANGARM64 ~/src/modernc.org/tk9.0/tcl9.0b3/win (dev)
$ gcc --version
clang version 19.1.0-rc3 (https://github.com/llvm/llvm-project.git
437434df21d839becb453f6821564662e9824f02)
Target: aarch64-w64-windows-gnu
Thread model: posix
InstalledDir: C:/mingw/bin

jnml@pi64 CLANGARM64 ~/src/modernc.org/tk9.0/tcl9.0b3/win (dev)
$

FTR: Tcl build of the same Tcl version works with no issues using
mingw on Windows 10/{amd64,386}. As well as tk9.0b3.

-j