sys/tiny_strerror: fix compilation with picolibc on Ubuntu

[maribu]

Contribution description

The picolibc shipped in Ubuntu does not provided non-POSIX errnos by default. If the errno codes are not provided, we can also not provide corresponding strings.

This guards the effected strings corresponding to non-POSIX errnos behind #ifdef, so that they are only provided when the corresponding errno is.

Testing procedure

$ FEATURES_REQUIRED=picolibc make BOARD=nucleo-f767zi -C tests/periph/selftest_shield

on Ubuntu with master gives:

/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:146:6: error: 'EHOSTDOWN' undeclared here (not in a function); did you mean 'ENETDOWN'?
  146 |     [EHOSTDOWN]         = _ehostdown,
      |      ^~~~~~~~~
      |      ENETDOWN
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:146:6: error: array index in initializer not of integer type
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:146:6: note: (near initialization for 'lookup')
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:176:27: error: initialized field overwritten [-Werror=override-init]
  176 |     [ENOSPC]            = _enospc,
      |                           ^~~~~~~
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:176:27: note: (near initialization for 'lookup[28]')
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:191:6: error: 'EPFNOSUPPORT' undeclared here (not in a function); did you mean 'EAFNOSUPPORT'?
  191 |     [EPFNOSUPPORT]      = _epfnosupport,
      |      ^~~~~~~~~~~~
      |      EAFNOSUPPORT
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:191:6: error: array index in initializer not of integer type
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:191:6: note: (near initialization for 'lookup')
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:191:27: error: initialized field overwritten [-Werror=override-init]
  191 |     [EPFNOSUPPORT]      = _epfnosupport,
      |                           ^~~~~~~~~~~~~
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:191:27: note: (near initialization for 'lookup[2]')
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:203:6: error: 'ETOOMANYREFS' undeclared here (not in a function)
  203 |     [ETOOMANYREFS]      = _etoomanyrefs,
      |      ^~~~~~~~~~~~
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:203:6: error: array index in initializer not of integer type
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:203:6: note: (near initialization for 'lookup')
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:203:27: error: initialized field overwritten [-Werror=override-init]
  203 |     [ETOOMANYREFS]      = _etoomanyrefs,
      |                           ^~~~~~~~~~~~~
/home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror/tiny_strerror.c:203:27: note: (near initialization for 'lookup[63]')

with this PR:

...
"make" -C /home/[email protected]/Repos/software/RIOT/master/sys/tiny_strerror
"make" -C /home/[email protected]/Repos/software/RIOT/master/sys/tsrb
   text	  data	   bss	   dec	   hex	filename
  13396	    44	  2400	 15840	  3de0	/home/[email protected]/Repos/software/RIOT/master/tests/periph/selftest_shield/bin/nucleo-f767zi/tests_selftest_shield.elf
make: Leaving directory '/home/[email protected]/Repos/software/RIOT/master/tests/periph/selftest_shield'

Issues/PRs references

None

[maribu]

@MrKevinWeiss Do you want this to be backported?

Compilation works fine with BUILD_IN_DOCKER=1; it only affects an older version of picolibc shipped in Ubuntu.

It certainly is a rather un-scary and trivial fix, though.

[riot-ci]

Murdock results

✔️ PASSED

28caf32 sys/tiny_strerror: fix compilation with picolibc on Ubuntu

Success	Failures	Total	Runtime
10271	0	10271	10m:47s

Artifacts

• Documentation preview