diff -urp a/lib/printf_test.c b/lib/printf_test.c
--- a/lib/printf_test.c	1970-01-01 00:00:00.000000000 +0000
+++ b/lib/printf_test.c	1970-01-01 00:00:00.000000000 +0000
@@ -33,10 +33,14 @@ t_simple(void)
   BSPRINTF(1, "\xff", buf, "%c", 0xff);
 
   errno = 5;
-  BSPRINTF(18, "Input/output error", buf, "%m");
+  // glibc returns "Input/output error" while musl-libc returns "I/O error"
+  //BSPRINTF(18, "Input/output error", buf, "%m");
+  BSPRINTF(9, "I/O error", buf, "%m");
   errno = 0;
 
-  BSPRINTF(18, "Input/output error", buf, "%M", 5);
+  // glibc returns "Input/output error" while musl-libc returns "I/O error"
+  //BSPRINTF(18, "Input/output error", buf, "%M", 5);
+  BSPRINTF(9, "I/O error", buf, "%M", 5);
 
   BSPRINTF(11, "TeSt%StRiNg", buf, "%s", "TeSt%StRiNg");