diff --git a/libvmaf/meson.build b/libvmaf/meson.build
index 82690668f..92e3adc87 100644
--- a/libvmaf/meson.build
+++ b/libvmaf/meson.build
@@ -20,15 +20,12 @@ libvmaf_inc = include_directories(['include'])
 
 # Arguments in test_args will be used even on feature tests
 test_args = []
-if host_machine.system() == 'linux'
+if host_machine.system() == 'linux' or host_machine.system() == 'windows'
     test_args += '-D_GNU_SOURCE'
     add_project_arguments('-D_GNU_SOURCE', language: 'c')
 elif host_machine.system() == 'darwin'
     test_args += '-D_DARWIN_C_SOURCE'
     add_project_arguments('-D_DARWIN_C_SOURCE', language: 'c')
-else
-    test_args += '-D_XOPEN_SOURCE=600'
-    add_project_arguments('-D_XOPEN_SOURCE=600', language: 'c')
 endif
 
 # Header checks