[Bug target/105506] Error building GCC 12.1.0 against MinGW-w64: fatal error: cannot execute 'cc1': CreateProcess: No such file or directory

[brechtsanders at users dot sourceforge.net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105506

--- Comment #4 from Brecht Sanders <brechtsanders at users dot sourceforge.net> ---
I just ran `gcc -print-prog-name=cc1` and saw the output was only `cc1` while
on working versions it reports a full path to `cc1.exe` (e.g.
`d:/prog/winlibs64_stage/custombuilt/share/gcc/bin/../libexec/gcc/x86_64-w64-mingw32/12.1.0/cc1.exe`).

In this minimal case Process Monitor also shows the handle to `cc1.exe` is
successfully opened but the subsequent calls to QueryInformationVolume and
QueryAllInformationFile fail with BUFFER_OVERFLOW.