Merge pull request #1159 from 64/c89-headers #4107

Job	Run time
Build mlibc (x86_64, mlibc, gcc)	3m 57s
Build mlibc (x86_64, mlibc-static, gcc)	3m 10s
Compile sysdeps (dripos)	2m 26s
Build mlibc (x86_64, mlibc-shared, gcc)	2m 58s
Compile sysdeps (lemon)	2m 48s
Build mlibc (x86_64, mlibc-ansi-only, gcc)	3m 23s
Compile sysdeps (aero)	2m 26s
Build mlibc (x86_64, mlibc-headers-only, gcc)	1m 59s
Compile sysdeps (ironclad)	2m 24s
Build mlibc (riscv64, mlibc, gcc)	3m 45s
Compile sysdeps (lyre)	2m 22s
Build mlibc (riscv64, mlibc-static, gcc)	4m 27s
Compile sysdeps (keyronex)	2m 44s
Build mlibc (riscv64, mlibc-shared, gcc)	3m 9s
Build mlibc (riscv64, mlibc-ansi-only, gcc)	2m 54s
Compile sysdeps (managarm)	2m 59s
Build mlibc (riscv64, mlibc-headers-only, gcc)	1m 57s
Compile sysdeps (vinix)	2m 27s
Build mlibc (aarch64, mlibc, gcc)	4m 4s
Compile sysdeps (astral)	2m 46s
Build mlibc (aarch64, mlibc-static, gcc)	3m 24s
Build mlibc (aarch64, mlibc-shared, gcc)	3m 41s
Build mlibc (aarch64, mlibc-ansi-only, gcc)	3m 33s
Build mlibc (aarch64, mlibc-headers-only, gcc)	2m 7s
Build mlibc (x86, mlibc, gcc)	4m 1s
Build mlibc (x86, mlibc-static, gcc)	3m 12s
Build mlibc (x86, mlibc-shared, gcc)	3m 17s
Build mlibc (x86, mlibc-ansi-only, gcc)	3m 16s
Build mlibc (x86, mlibc-headers-only, gcc)	2m 0s
Build mlibc (m68k, mlibc, gcc)	3m 31s
Build mlibc (m68k, mlibc-static, gcc)	2m 50s
Build mlibc (m68k, mlibc-shared, gcc)	2m 56s
Build mlibc (m68k, mlibc-ansi-only, gcc)	3m 11s
Build mlibc (m68k, mlibc-headers-only, gcc)	2m 2s
Build mlibc (x86_64, mlibc, clang)	3m 9s
	1h 45m 15s

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