diff --git a/include/err.h b/include/err.h
index 7c05cd1dbb..b9b7516287 100644
--- a/include/err.h
+++ b/include/err.h
@@ -12,12 +12,12 @@ __vwarn_internal (const char *format, __gnuc_va_list ap,
 
 # ifndef _ISOMAC
 
-libc_hidden_proto (warn)
-libc_hidden_proto (warnx)
-libc_hidden_proto (vwarn)
-libc_hidden_proto (vwarnx)
-libc_hidden_proto (verr)
-libc_hidden_proto (verrx)
+libc_hidden_ldbl_proto (warn)
+libc_hidden_ldbl_proto (warnx)
+libc_hidden_ldbl_proto (vwarn)
+libc_hidden_ldbl_proto (vwarnx)
+libc_hidden_ldbl_proto (verr)
+libc_hidden_ldbl_proto (verrx)
 
 # endif /* !_ISOMAC */
 #endif /* err.h */
diff --git a/include/libc-symbols.h b/include/libc-symbols.h
index b0b75a087e..3555cb6f3d 100644
--- a/include/libc-symbols.h
+++ b/include/libc-symbols.h
@@ -885,6 +885,8 @@ for linking")
 #define libc_hidden_builtin_def(name) libc_hidden_def (name)
 #define libc_hidden_builtin_weak(name) libc_hidden_weak (name)
 #define libc_hidden_builtin_ver(local, name) libc_hidden_ver (local, name)
+
+#define libc_hidden_ldbl_proto(name, attrs...) libc_hidden_proto (name, ##attrs)
 #ifdef __ASSEMBLER__
 # define HIDDEN_BUILTIN_JUMPTARGET(name) HIDDEN_JUMPTARGET(name)
 #endif
diff --git a/include/stdio.h b/include/stdio.h
index dffa7765dd..6718af4108 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -9,13 +9,24 @@
 
 /* Now define the internal interfaces.  */
 
+/*  Some libc_hidden_ldbl_proto's do not map to a unique symbol when
+    redirecting ldouble to _Float128 variants.  We can therefore safely
+    directly alias them to their internal name.  */
+# if __LONG_DOUBLE_USES_FLOAT128 == 1 && IS_IN (libc)
+#  define stdio_hidden_ldbl_proto(p, f) \
+  extern __typeof (p ## f) p ## f __asm (__ASMNAME ("___ieee128_" #f));
+# elif __LONG_DOUBLE_USES_FLOAT128 == 1
+#  define stdio_hidden_ldbl_proto(p,f) __LDBL_REDIR1_DECL (p ## f, p ## f ## ieee128)
+# else
+#  define stdio_hidden_ldbl_proto(p,f) libc_hidden_proto (p ## f)
+# endif
+
 extern int __fcloseall (void) attribute_hidden;
 extern int __snprintf (char *__restrict __s, size_t __maxlen,
 		       const char *__restrict __format, ...)
      __attribute__ ((__format__ (__printf__, 3, 4)));
-#  if __LONG_DOUBLE_USES_FLOAT128 == 0
-libc_hidden_proto (__snprintf)
-#  endif
+stdio_hidden_ldbl_proto (__, snprintf)
+
 extern int __vfscanf (FILE *__restrict __s,
 		      const char *__restrict __format,
 		      __gnuc_va_list __arg)
@@ -66,6 +77,7 @@ extern int __isoc99_vscanf (const char *__restrict __format,
 extern int __isoc99_vsscanf (const char *__restrict __s,
 			     const char *__restrict __format,
 			     __gnuc_va_list __arg) __THROW;
+
 libc_hidden_proto (__isoc99_sscanf)
 libc_hidden_proto (__isoc99_vsscanf)
 libc_hidden_proto (__isoc99_vfscanf)
@@ -74,12 +86,25 @@ libc_hidden_proto (__isoc99_vfscanf)
    Unfortunately, symbol redirection is not transitive, so the
    __REDIRECT in the public header does not link up with the above
    libc_hidden_proto.  Bridge the gap with a macro.  */
-#  if !__GLIBC_USE (DEPRECATED_SCANF) \
-      && __LONG_DOUBLE_USES_FLOAT128 == 0
+#  if !__GLIBC_USE (DEPRECATED_SCANF)
 #   undef sscanf
 #   define sscanf __isoc99_sscanf
 #  endif
 
+#  if __LONG_DOUBLE_USES_FLOAT128 == 1  && IS_IN (libc)
+/* These are implemented as redirects to other public API.
+   Therefore, the usual redirection fails to avoid PLT.  */
+extern __typeof (__isoc99_sscanf) ___ieee128_isoc99_sscanf __THROW;
+extern __typeof (__isoc99_vsscanf) ___ieee128_isoc99_vsscanf __THROW;
+extern __typeof (__isoc99_vfscanf) ___ieee128_isoc99_vfscanf __THROW;
+libc_hidden_proto (___ieee128_isoc99_sscanf)
+libc_hidden_proto (___ieee128_isoc99_vsscanf)
+libc_hidden_proto (___ieee128_isoc99_vfscanf)
+#define __isoc99_sscanf ___ieee128_isoc99_sscanf
+#define __isoc99_vsscanf ___ieee128_isoc99_vsscanf
+#define __isoc99_vfscanf ___ieee128_isoc99_vfscanf
+#  endif
+
 /* Prototypes for compatibility functions.  */
 extern FILE *__new_tmpfile (void);
 extern FILE *__old_tmpfile (void);
@@ -153,9 +178,8 @@ libc_hidden_proto (__libc_readline_unlocked);
 extern const char *const _sys_errlist_internal[] attribute_hidden;
 extern int _sys_nerr_internal attribute_hidden;
 
-#if __LONG_DOUBLE_USES_FLOAT128 == 0
-libc_hidden_proto (__asprintf)
-#endif
+libc_hidden_ldbl_proto (__asprintf)
+
 #  if IS_IN (libc)
 extern FILE *_IO_new_fopen (const char*, const char*);
 #   define fopen(fname, mode) _IO_new_fopen (fname, mode)
@@ -178,13 +202,11 @@ extern int _IO_new_fgetpos (FILE *, __fpos_t *);
 
 extern __typeof (dprintf) __dprintf
      __attribute__ ((__format__ (__printf__, 2, 3)));
-libc_hidden_proto (__dprintf)
-#if __LONG_DOUBLE_USES_FLOAT128 == 0
-libc_hidden_proto (dprintf)
-libc_hidden_proto (fprintf)
-libc_hidden_proto (vfprintf)
-libc_hidden_proto (sprintf)
-#endif
+stdio_hidden_ldbl_proto (__, dprintf)
+libc_hidden_ldbl_proto (dprintf)
+libc_hidden_ldbl_proto (fprintf)
+libc_hidden_ldbl_proto (vfprintf)
+libc_hidden_ldbl_proto (sprintf)
 libc_hidden_proto (fwrite)
 libc_hidden_proto (perror)
 libc_hidden_proto (remove)
diff --git a/include/sys/cdefs.h b/include/sys/cdefs.h
index 524fe57a25..9f44ac5a0a 100644
--- a/include/sys/cdefs.h
+++ b/include/sys/cdefs.h
@@ -13,6 +13,26 @@ extern void __chk_fail (void) __attribute__ ((__noreturn__));
 libc_hidden_proto (__chk_fail)
 rtld_hidden_proto (__chk_fail)
 
-#endif
+/* If we are using redirects internally to support long double,
+   we need to tweak some macros to ensure the PLT bypass tricks
+   continue to work in libc. */
+#if __LONG_DOUBLE_USES_FLOAT128 == 1 && IS_IN (libc) && defined SHARED
+
+# undef __LDBL_REDIR_DECL
+# define __LDBL_REDIR_DECL(func) \
+   extern __typeof(func) func __asm (__ASMNAME ("__GI____ieee128_" #func));
+
+# undef libc_hidden_ldbl_proto
+# define libc_hidden_ldbl_proto(func, attrs...) \
+   extern __typeof(func) ___ieee128_ ## func; \
+   libc_hidden_proto (___ieee128_ ## func, ##attrs);
+
+# undef __LDBL_REDIR2_DECL
+# define __LDBL_REDIR2_DECL(func) \
+   extern __typeof(__ ## func) __ ## func __asm (__ASMNAME ("__GI____ieee128___" #func));
+
+#endif
+
+#endif /* !defined _ISOMAC */
 
 #endif
diff --git a/include/sys/syslog.h b/include/sys/syslog.h
index 89d3479ebc..44422eab13 100644
--- a/include/sys/syslog.h
+++ b/include/sys/syslog.h
@@ -3,7 +3,7 @@
 #include <misc/sys/syslog.h>
 #ifndef _ISOMAC
 
-libc_hidden_proto (syslog)
+libc_hidden_ldbl_proto (syslog)
 
 /* __vsyslog_internal uses the same mode_flags bits as
    __v*printf_internal; see libio/libioP.h.  */
diff --git a/include/wchar.h b/include/wchar.h
index c792b38943..617906eb14 100644
--- a/include/wchar.h
+++ b/include/wchar.h
@@ -64,7 +64,7 @@ libc_hidden_proto (__wcstoul_internal)
 libc_hidden_proto (__wcstoull_internal)
 libc_hidden_proto (wcstof)
 libc_hidden_proto (wcstod)
-libc_hidden_proto (wcstold)
+libc_hidden_ldbl_proto (wcstold)
 libc_hidden_proto (wcstol)
 libc_hidden_proto (wcstoll)
 libc_hidden_proto (wcstoul)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-asprintf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-asprintf.c
index 68cafbb2fa..2a6ed2f813 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-asprintf.c
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-asprintf.c
@@ -20,7 +20,7 @@
 #include <libio/libioP.h>
 
 extern int
-___ieee128_asprintf (char **string_ptr, const char *format, ...)
+___ieee128___asprintf (char **string_ptr, const char *format, ...)
 {
   va_list ap;
   int done;
@@ -32,4 +32,5 @@ ___ieee128_asprintf (char **string_ptr, const char *format, ...)
 
   return done;
 }
-strong_alias (___ieee128_asprintf, __asprintfieee128)
+hidden_def (___ieee128___asprintf)
+strong_alias (___ieee128___asprintf, __asprintfieee128)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-dprintf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-dprintf.c
index 9dc65309bd..87440c9850 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-dprintf.c
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-dprintf.c
@@ -32,3 +32,4 @@ ___ieee128_dprintf (int d, const char *format, ...)
   return done;
 }
 strong_alias (___ieee128_dprintf, __dprintfieee128)
+hidden_def (___ieee128_dprintf);
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-err.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-err.c
index eae071b9c4..f81d3edcbf 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-err.c
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-err.c
@@ -91,3 +91,10 @@ IEEE128_DECL (errx) (int status, const char *format, ...)
   VA (verrx (status, format, ap))
 }
 IEEE128_ALIAS (errx)
+
+hidden_def (___ieee128_warn)
+hidden_def (___ieee128_warnx)
+hidden_def (___ieee128_vwarn)
+hidden_def (___ieee128_vwarnx)
+hidden_def (___ieee128_verr)
+hidden_def (___ieee128_verrx)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-fprintf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-fprintf.c
index e1c989643e..b05e6f1bc6 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-fprintf.c
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-fprintf.c
@@ -32,3 +32,4 @@ ___ieee128_fprintf (FILE *fp, const char *format, ...)
   return done;
 }
 strong_alias (___ieee128_fprintf, __fprintfieee128)
+hidden_def (___ieee128_fprintf)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_sscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_sscanf.c
index bfc7270a78..cd1c9fa333 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_sscanf.c
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_sscanf.c
@@ -37,3 +37,4 @@ ___ieee128_isoc99_sscanf (const char *string, const char *format, ...)
   return done;
 }
 strong_alias (___ieee128_isoc99_sscanf, __isoc99_sscanfieee128)
+hidden_def (___ieee128_isoc99_sscanf)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vfscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vfscanf.c
index b561fa3044..2a11f49ea6 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vfscanf.c
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vfscanf.c
@@ -17,6 +17,7 @@
    <https://www.gnu.org/licenses/>.  */
 
 #include <libio/libioP.h>
+#include <stdio.h>
 
 extern int
 ___ieee128_isoc99_vfscanf (FILE *fp, const char *format, va_list ap)
@@ -25,3 +26,4 @@ ___ieee128_isoc99_vfscanf (FILE *fp, const char *format, va_list ap)
   return __vfscanf_internal (fp, format, ap, mode_flags);
 }
 strong_alias (___ieee128_isoc99_vfscanf, __isoc99_vfscanfieee128)
+hidden_def (___ieee128_isoc99_vfscanf)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vsscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vsscanf.c
index bef6ebcce0..d976cdbe1f 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vsscanf.c
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vsscanf.c
@@ -28,3 +28,4 @@ ___ieee128_isoc99_vsscanf (const char *string, const char *format, va_list ap)
   return __vfscanf_internal (fp, format, ap, mode_flags);
 }
 strong_alias (___ieee128_isoc99_vsscanf, __isoc99_vsscanfieee128)
+hidden_def (___ieee128_isoc99_vsscanf)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-sprintf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-sprintf.c
index 52088cd576..690dc3abf1 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-sprintf.c
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-sprintf.c
@@ -33,3 +33,4 @@ ___ieee128_sprintf (char *s, const char *format, ...)
   return done;
 }
 strong_alias (___ieee128_sprintf, __sprintfieee128)
+hidden_def (___ieee128_sprintf)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-syslog.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-syslog.c
index 914f24aebd..4af546326c 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-syslog.c
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-syslog.c
@@ -30,6 +30,7 @@ ___ieee128_syslog (int pri, const char *fmt, ...)
   va_end (ap);
 }
 strong_alias (___ieee128_syslog, __syslogieee128)
+hidden_def (___ieee128_syslog)
 
 void
 ___ieee128_vsyslog (int pri, const char *fmt, va_list ap)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-vfprintf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-vfprintf.c
index 234cd9de8d..b407eae969 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-vfprintf.c
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-vfprintf.c
@@ -24,3 +24,4 @@ ___ieee128_vfprintf (FILE *fp, const char *format, va_list ap)
   return __vfprintf_internal (fp, format, ap, PRINTF_LDBL_USES_FLOAT128);
 }
 strong_alias (___ieee128_vfprintf, __vfprintfieee128)
+hidden_def (___ieee128_vfprintf)
diff --git a/sysdeps/ieee754/ldbl-128ibm/include/bits/iscanonical.h b/sysdeps/ieee754/ldbl-128ibm/include/bits/iscanonical.h
index bee080bd29..8cbd6f74bf 100644
--- a/sysdeps/ieee754/ldbl-128ibm/include/bits/iscanonical.h
+++ b/sysdeps/ieee754/ldbl-128ibm/include/bits/iscanonical.h
@@ -1,5 +1,5 @@
 #include_next <bits/iscanonical.h>
 
-#ifndef _ISOMAC
+#if !defined _ISOMAC && (__LONG_DOUBLE_USES_FLOAT128 == 0)
 libm_hidden_proto (__iscanonicall)
 #endif