adapt header for cc

[ben-schwen]

Closes #7512

Follows #7428 since I cannot cc() after that

gcc -I"/usr/share/R/include" -DNDEBUG      -fopenmp  -fpic  -fopenmp -std=c11 -O3 -pipe -Wall -pedantic -Wstrict-prototypes -isystem /usr/share/R/include  -fno-common -c utils.c -o utils.o
gcc -I"/usr/share/R/include" -DNDEBUG      -fopenmp  -fpic  -fopenmp -std=c11 -O3 -pipe -Wall -pedantic -Wstrict-prototypes -isystem /usr/share/R/include  -fno-common -c vecseq.c -o vecseq.o
gcc -I"/usr/share/R/include" -DNDEBUG      -fopenmp  -fpic  -fopenmp -std=c11 -O3 -pipe -Wall -pedantic -Wstrict-prototypes -isystem /usr/share/R/include  -fno-common -c wrappers.c -o wrappers.o
utils.c: In function ‘is_direct_child’:
utils.c:692:3: error: unknown type name ‘siginfo_t’
  692 |   siginfo_t info;
      |   ^~~~~~~~~
utils.c:694:15: warning: implicit declaration of function ‘waitid’; did you mean ‘waitpid’? [-Wimplicit-function-declaration]
  694 |     pret[i] = waitid(P_PID, ppids[i], &info, WCONTINUED | WEXITED | WNOHANG | WNOWAIT | WSTOPPED) == 0;
      |               ^~~~~~
      |               waitpid
utils.c:694:22: error: ‘P_PID’ undeclared (first use in this function)
  694 |     pret[i] = waitid(P_PID, ppids[i], &info, WCONTINUED | WEXITED | WNOHANG | WNOWAIT | WSTOPPED) == 0;
      |                      ^~~~~
utils.c:694:22: note: each undeclared identifier is reported only once for each function it appears in
utils.c:694:46: error: ‘WCONTINUED’ undeclared (first use in this function)
  694 |     pret[i] = waitid(P_PID, ppids[i], &info, WCONTINUED | WEXITED | WNOHANG | WNOWAIT | WSTOPPED) == 0;
      |                                              ^~~~~~~~~~
utils.c:694:59: error: ‘WEXITED’ undeclared (first use in this function); did you mean ‘WIFEXITED’?
  694 |     pret[i] = waitid(P_PID, ppids[i], &info, WCONTINUED | WEXITED | WNOHANG | WNOWAIT | WSTOPPED) == 0;
      |                                                           ^~~~~~~
      |                                                           WIFEXITED
utils.c:694:79: error: ‘WNOWAIT’ undeclared (first use in this function)
  694 |     pret[i] = waitid(P_PID, ppids[i], &info, WCONTINUED | WEXITED | WNOHANG | WNOWAIT | WSTOPPED) == 0;
      |                                                                               ^~~~~~~
utils.c:694:89: error: ‘WSTOPPED’ undeclared (first use in this function); did you mean ‘WIFSTOPPED’?
  694 |     pret[i] = waitid(P_PID, ppids[i], &info, WCONTINUED | WEXITED | WNOHANG | WNOWAIT | WSTOPPED) == 0;
      |                                                                                         ^~~~~~~~
      |                                                                                         WIFSTOPPED

[aitap]

This may work with an older value of the feature test macro (e.g. POSIX.1-2001, so 200112L), but this is good enough and unbreaks cc() for you right now.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.04%. Comparing base (dc1dbe9) to head (840deae).
⚠️ Report is 6 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #7499   +/-   ##
=======================================
  Coverage   99.04%   99.04%           
=======================================
  Files          87       87           
  Lines       16694    16707   +13     
=======================================
+ Hits        16534    16547   +13     
  Misses        160      160           

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[github-actions]

• HEAD=define_posix stopped early for isoweek improved in #7144
  

Generated via commit 840deae

Download link for the artifact containing the test results: ↓ atime-results.zip

Task	Duration
R setup and installing dependencies	2 minutes and 47 seconds
Installing different package versions	45 seconds
Running and plotting the test cases	4 minutes and 51 seconds

[aitap]

Manual testing shows that POSIX.1-2001 feature test macro is not enough; it has to be POSIX.1-2008 or newer.