[PATCH] mksysinfo: add support for musl libc

[soeren@soeren-tempel.net]

From: Sören Tempel <soeren@soeren-tempel.net>

This patch addresses two minor compatibility issues with musl libc:

* On some architecture (e.g. PowerPC), musl has more than one field
  prefixed with st_{a,m,c}tim in struct stat. This causes the sed(1)
  invocation to not work correctly (since it will only replace the first
  occurrence) [1]. This can be fixed by passing the 'g' flag to replace
  all occurrences.
* Since version 1.2.3, musl defines SYS_SECCOMP in signal.h [2]. This
  conflicts with mksysinfo extraction of syscall numbers [3]. By
  restricting the grep expression to only match lower case characters we
  can avoid a redefinition of SYS_SECCOMP. This is GCC PR 105225.

This patch combines two Alpine Linux patches which have been written by
Ariadne Conill and Natanael Copa. I haven't tested this with glibc but I
strongly suspect that both changes should not introduce any issue with
glibc.

[1]: https://git.musl-libc.org/cgit/musl/tree/arch/powerpc/bits/stat.h
[2]: https://git.musl-libc.org/cgit/musl/commit/?id=3dcbd896907d9d474da811b7c6b769342abaf651
[3]: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105225

Signed-off-by: Sören Tempel <soeren@soeren-tempel.net>
---
 libgo/mksysinfo.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libgo/mksysinfo.sh b/libgo/mksysinfo.sh
index 5aa30915..72044624 100755
--- a/libgo/mksysinfo.sh
+++ b/libgo/mksysinfo.sh
@@ -126,7 +126,7 @@ if ! grep '^const SIGCLD ' ${OUT} >/dev/null 2>&1; then
 fi
 
 # The syscall numbers.  We force the names to upper case.
-grep '^const _SYS_' gen-sysinfo.go | \
+grep '^const _SYS_[a-z]' gen-sysinfo.go | \
   sed -e 's/const _\(SYS_[^= ]*\).*$/\1/' | \
   while read sys; do
     sup=`echo $sys | tr abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ`
@@ -506,7 +506,7 @@ fi
 
 # For historical reasons Go uses the suffix "timespec" instead of "tim" for
 # stat_t's time fields on NetBSD.
-st_times='-e s/st_atim/Atim/ -e s/st_mtim/Mtim/ -e s/st_ctim/Ctim/'
+st_times='-e s/st_atim/Atim/g -e s/st_mtim/Mtim/g -e s/st_ctim/Ctim/g'
 if test "${GOOS}" = "netbsd"; then
     st_times='-e s/st_atim/Atimespec/ -e s/st_mtim/Mtimespec/ -e s/st_ctim/Ctimespec/'
 fi