--- a/sysdeps/sh/sh4/fpu/fpu_control.h
+++ b/sysdeps/sh/sh4/fpu/fpu_control.h
@@ -45,6 +45,14 @@
 #define _FPU_GETCW(cw) __asm__ ("sts fpscr,%0" : "=r" (cw))
 
 #if defined __GNUC__
+/* Allow the use in C++ code.  */
+#ifdef __cplusplus
+extern "C" {
+#endif
+extern void __set_fpscr(unsigned long);
+#ifdef __cplusplus
+}
+#endif  /* C++ */
 #define _FPU_SETCW(cw) __set_fpscr ((cw))
 #else
 #define _FPU_SETCW(cw) __asm__ ("lds %0,fpscr" : : "r" (cw))