diff --git a/components/libc/posix/io/termios/termios.c b/components/libc/posix/io/termios/termios.c
index 8333b594bf..84061079d9 100644
--- a/components/libc/posix/io/termios/termios.c
+++ b/components/libc/posix/io/termios/termios.c
@@ -111,7 +111,6 @@ int tcdrain(int fd)
     return 0;
 }
 
-#if defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
 void cfmakeraw(struct termios *t)
 {
     t->c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP|INLCR|IGNCR|ICRNL|IXON);
@@ -127,4 +126,3 @@ int cfsetspeed(struct termios *tio, speed_t speed)
 {
     return cfsetospeed(tio, speed);
 }
-#endif
diff --git a/components/libc/posix/io/termios/termios.h b/components/libc/posix/io/termios/termios.h
index 27f2db85b0..8553b01918 100644
--- a/components/libc/posix/io/termios/termios.h
+++ b/components/libc/posix/io/termios/termios.h
@@ -202,10 +202,8 @@ int tcflow (int, int);
 
 pid_t tcgetsid (int);
 
-#if defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
 void cfmakeraw(struct termios *);
 int cfsetspeed(struct termios *, speed_t);
-#endif
 
 #ifdef __cplusplus
 }