Index: gcc-6-6.4.0/src/libgo/mksysinfo.sh
===================================================================
--- gcc-6-6.4.0.orig/src/libgo/mksysinfo.sh
+++ gcc-6-6.4.0/src/libgo/mksysinfo.sh
@@ -304,6 +304,13 @@ echo '#include <errno.h>' | ${CC} -x c -
   egrep '#define E[A-Z0-9_]+ ' | \
   sed -e 's/^#define \(E[A-Z0-9_]*\) .*$/const \1 = Errno(_\1)/' >> ${OUT}
 
+# Special treatment of EWOULDBLOCK for GNU/Hurd
+# /usr/include/bits/errno.h: #define EWOULDBLOCK EAGAIN
+if egrep 'define EWOULDBLOCK EAGAIN' gen-sysinfo.go > /dev/null 2>&1; then
+  egrep '^const EWOULDBLOCK = Errno(_EWOULDBLOCK)' ${OUT} | \
+    sed -i -e 's/_EWOULDBLOCK/_EAGAIN/' ${OUT}
+fi
+
 # The O_xxx flags.
 egrep '^const _(O|F|FD)_' gen-sysinfo.go | \
   sed -e 's/^\(const \)_\([^= ]*\)\(.*\)$/\1\2 = _\2/' >> ${OUT}
@@ -362,6 +369,11 @@ grep '^const _SYS_' gen-sysinfo.go | \
     echo "const $sup = _$sys" >> ${OUT}
   done
 
+# Special treatment of SYS_IOCTL for GNU/Hurd
+if ! grep '^const SYS_IOCTL' ${OUT} > /dev/null 2>&1; then
+  echo "const SYS_IOCTL = 0" >> ${OUT}
+fi
+
 # The GNU/Linux support wants to use SYS_GETDENTS64 if available.
 if ! grep '^const SYS_GETDENTS ' ${OUT} >/dev/null 2>&1; then
   echo "const SYS_GETDENTS = 0" >> ${OUT}
@@ -676,6 +688,11 @@ grep '^type _tms ' gen-sysinfo.go | \
 
 # The stat type.
 # Prefer largefile variant if available.
+# Special treatment of st_dev for GNU/Hurd
+# /usr/include/i386-gnu/bits/stat.h: #define st_dev st_fsid
+if grep 'define st_dev st_fsid' gen-sysinfo.go > /dev/null 2>&1; then
+  sed -i -e 's/; st_fsid/; st_dev/' gen-sysinfo.go
+fi
 stat=`grep '^type _stat64 ' gen-sysinfo.go || true`
 if test "$stat" != ""; then
   grep '^type _stat64 ' gen-sysinfo.go