build: support GNU Hurd by skipping BSD sysctl checks #38975

Problem:
Neovim currently fails to build on GNU Hurd. Because Hurd relies on
glibc, `<sys/param.h>` defines the `BSD` macro for 4.4BSD compatibility.
The preprocessor incorrectly routes Hurd into the BSD code paths, which
fatally fail during compilation because Hurd lacks `<sys/sysctl.h>` and
the `sysctl()` function.

Solution:
Update the preprocessor guards in  `os/proc.c` to explicitly exclude
`__gnu_hurd__` from the BSD-specific `sysctl` blocks. Instead, group GNU
Hurd with the `__linux__` paths, as both systems rely on standard POSIX
interfaces and `/proc` parsing (which Hurd fully supports via its
`procfs` translator).

Testing:
The test suite does not fully pass yet natively on GNU Hurd
(specifically tests involving PTY closures and SIGHUP/SIGTERM trapping,
like `autocmd TermClose kills PTY job`). This is due to underlying
differences in Hurd's Mach RPC architecture and the `term` translator.
This patch does not attempt to fix those test executions, but simply
unblocks the core compiler as a necessary first step.

0 files changed, 0 insertions, 0 deletions