add compiler args for strptime

include/strptime.h

@@ -1,8 +1,11 @@
 #ifndef STRPTIME_H
 #define STRPTIME_H
 
+#ifndef HAS_STRPTIME
 #include <time.h>
 
 char *strptime(const char *s, const char *format, struct tm *tm);
 
+#endif // HAS_STRPTIME
+
 #endif // STRPTIME_H

meson.build

@@ -64,6 +64,9 @@ if cc.get_id() == 'msvc'
     add_project_arguments('/utf-8', language: 'c')
 else
     add_project_link_arguments('-no-pie', language: 'c')
+
+    # Needed to make GCC happy with `strptime`
+    add_project_arguments('-D_XOPEN_SOURCE', '-D_GNU_SOURCE', language : 'c')
 endif
 
 build_defines = []

src/core.c

@@ -2,6 +2,7 @@
 
 #include "astro.h"
 #include "parse_BSC5.h"
+#include "strptime.h"
 
 #include <math.h>
 #include <stdio.h>

src/meson.build

@@ -25,5 +25,6 @@ if not has_strptime
 )
 else
   message('strptime is available, no need for local implementation.')
+  build_defines += '-DHAS_STRPTIME'
   lib_strptime = []
 endif