Re: Patch for gcc-10.3.0

[Jim Wilson <jimw@sifive.com>]

On Mon, Apr 12, 2021 at 5:30 AM Jonathan Wakely via Gcc-help <
gcc-help@gcc.gnu.org> wrote:

> On Mon, 12 Apr 2021 at 13:10, John Hendry wrote:
> >                 I'm trying to install gcc-10.3.0 on a 64-bit PC running
> Crux Linux 3.5.  Make gives the error "bit_AVX512VPTINTERSECT not declared"
> in cpuinfo.c, line 392 or so, and then AVX512BF16 is not declared 4 lines
> later.
>
> The bit_AVX512VP2INTERSECT constant is defined in the cpuid.h header
> in the same directory.
>

But note that there is more than one cpuid.h file on the system, as there
is also one provided by the OS and/or system compiler, and possibly also by
cross compilers.  I've seen this problem happen for people that have
environment variables set that they forgot about, which are causing the
wrong cpuid.h file to be used.  Or maybe you are using a compiler with a
modified specs file, or maybe something else is going wrong.  The system
compiler one is probably older than the gcc version you are trying to
compile, and hence is missing all of the new entries in the file.  This
macro is new in gcc-10, and thus would not be present in a gcc-9 or earlier
cpuid.h file.  So you need to look at the compiler command for the cpuid.c
file and figure out why it is using the wrong cpuid.h file.  You can use
--save-temps to generate a .i file that will show which cpuid.h file is
being used.  You can add -v to see what header file paths are being used
during the compilation.    You can use --print-search-dirs to see what the
default search paths are.  printenv will show you what environment
variables are set.

Jim