Just guessing, but looking at the comment "linux-api-headers->glibc->binutils->gcc->binutils->glibc" and the dates that these packages are rebuilt on, it seems like the work to update linux-api-headers is substantial.
Re: [arch-general] Linux-api-headers out of date (4.17 vs 5.0)
Joel Teichroeb via arch-general Wed, 20 Mar 2019 19:43:56 -0700
- [arch-general] Linux-api-headers out of da... Jason Koch
- Re: [arch-general] Linux-api-headers ... Joel Teichroeb via arch-general