On 8/17/23 08:57, Eric Blake wrote:
m4 is single-threaded, so an asynsafe-spin operation is not going to be vital to performance
Gnulib has various options for omitting unnecessary locking code in single-threaded apps. If you have time, you might investigate why that is not happening for GNU m4. This should improve performance on most platforms, which would be worth doing even if Solaris 7 is no longer supported. And it should also fix this Solaris 7 porting glitch as a side effect.
