diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/Makefile b/sysdeps/ieee754/ldbl-128ibm-compat/Makefile
index ed0e2ec098..1f944806e7 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/Makefile
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/Makefile
@@ -6,6 +6,15 @@ ldbl-extra-routines += fwscanf \
 		       vwscanf
 endif
 
+ifeq ($(subdir),wcsmbs)
+ldbl-extra-routines += isoc99_fwscanf \
+		       isoc99_swscanf \
+		       isoc99_wscanf \
+		       isoc99_vfwscanf \
+		       isoc99_vswscanf \
+		       isoc99_vwscanf
+endif
+
 ifeq ($(subdir),stdio-common)
 ldbl-extra-routines += printf_size \
 		       asprintf \
@@ -32,7 +41,13 @@ ldbl-extra-routines += printf_size \
 		       vfscanf \
 		       vscanf \
 		       vsscanf \
-		       vfwscanf
+		       vfwscanf \
+		       isoc99_fscanf \
+		       isoc99_scanf \
+		       isoc99_sscanf \
+		       isoc99_vfscanf \
+		       isoc99_vscanf \
+		       isoc99_vsscanf
 
 # Printing long double values with IEEE binary128 format reuses part
 # of the internal float128 implementation (__printf_fp, __printf_fphex,
@@ -67,12 +82,30 @@ CFLAGS-test-wscanf-ibm128.c += -mabi=ibmlongdouble -Wno-psabi
 
 $(objpfx)test-wscanf-ieee128: gnulib-tests += $(f128-loader-link)
 
+tests-internal += test-isoc99-scanf-ieee128 test-isoc99-scanf-ibm128
+CFLAGS-test-isoc99-scanf-ieee128.c += -mfloat128 -mabi=ieeelongdouble -Wno-psabi -std=c99
+CFLAGS-test-isoc99-scanf-ibm128.c += -mabi=ibmlongdouble -Wno-psabi -std=c99
+
+$(objpfx)test-isoc99-scanf-ieee128: gnulib-tests += $(f128-loader-link)
+
+tests-internal += test-isoc99-wscanf-ieee128 test-isoc99-wscanf-ibm128
+CFLAGS-test-isoc99-wscanf-ieee128.c += -mfloat128 -mabi=ieeelongdouble -Wno-psabi -std=c99
+CFLAGS-test-isoc99-wscanf-ibm128.c += -mabi=ibmlongdouble -Wno-psabi -std=c99
+
+$(objpfx)test-isoc99-wscanf-ieee128: gnulib-tests += $(f128-loader-link)
+
 ifeq ($(run-built-tests),yes)
 tests-special += $(objpfx)test-scanf-ieee128.out
 tests-special += $(objpfx)test-scanf-ibm128.out
 
 tests-special += $(objpfx)test-wscanf-ieee128.out
 tests-special += $(objpfx)test-wscanf-ibm128.out
+
+tests-special += $(objpfx)test-isoc99-scanf-ieee128.out
+tests-special += $(objpfx)test-isoc99-scanf-ibm128.out
+
+tests-special += $(objpfx)test-isoc99-wscanf-ieee128.out
+tests-special += $(objpfx)test-isoc99-wscanf-ibm128.out
 endif
 
 $(objpfx)test-scanf-ieee128.out: \
@@ -99,6 +132,30 @@ $(objpfx)test-wscanf-ibm128.out: \
 	$(SHELL) $^ '$(test-program-prefix)' $@; \
 	$(evaluate-test)
 
+$(objpfx)test-isoc99-scanf-ieee128.out: \
+  ../sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ldbl-compat.sh \
+  $(objpfx)test-isoc99-scanf-ieee128
+	$(SHELL) $^ '$(test-program-prefix)' $@; \
+	$(evaluate-test)
+
+$(objpfx)test-isoc99-scanf-ibm128.out: \
+  ../sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ldbl-compat.sh \
+  $(objpfx)test-isoc99-scanf-ibm128
+	$(SHELL) $^ '$(test-program-prefix)' $@; \
+	$(evaluate-test)
+
+$(objpfx)test-isoc99-wscanf-ieee128.out: \
+  ../sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ldbl-compat.sh \
+  $(objpfx)test-isoc99-wscanf-ieee128
+	$(SHELL) $^ '$(test-program-prefix)' $@; \
+	$(evaluate-test)
+
+$(objpfx)test-isoc99-wscanf-ibm128.out: \
+  ../sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ldbl-compat.sh \
+  $(objpfx)test-isoc99-wscanf-ibm128
+	$(SHELL) $^ '$(test-program-prefix)' $@; \
+	$(evaluate-test)
+
 tests-internal += test-printf-size-ieee128 test-printf-size-ibm128
 CFLAGS-test-printf-size-ieee128.c += -mfloat128 -mabi=ieeelongdouble -Wno-psabi
 CFLAGS-test-printf-size-ibm128.c += -mabi=ibmlongdouble -Wno-psabi
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/Versions b/sysdeps/ieee754/ldbl-128ibm-compat/Versions
index dead38cdcb..23c2fd9793 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/Versions
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/Versions
@@ -181,6 +181,22 @@ libc {
     __vswscanfieee128;
     __vwscanfieee128;
 
+    __isoc99_fscanfieee128;
+    __isoc99_scanfieee128;
+    __isoc99_sscanfieee128;
+
+    __isoc99_vfscanfieee128;
+    __isoc99_vscanfieee128;
+    __isoc99_vsscanfieee128;
+
+    __isoc99_fwscanfieee128;
+    __isoc99_swscanfieee128;
+    __isoc99_wscanfieee128;
+
+    __isoc99_vfwscanfieee128;
+    __isoc99_vswscanfieee128;
+    __isoc99_vwscanfieee128;
+
     __argp_errorieee128;
     __argp_failureieee128;
 
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_fscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_fscanf.c
new file mode 100644
index 0000000000..3930170878
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_fscanf.c
@@ -0,0 +1,35 @@
+/* Wrapper for __isoc99_fscanf.  IEEE128 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stdarg.h>
+#include <libio/libioP.h>
+
+extern int
+___ieee128_isoc99_fscanf (FILE *fp, const char *format, ...)
+{
+  va_list arg;
+  int done;
+  int mode_flags = SCANF_ISOC99_A | SCANF_LDBL_USES_FLOAT128;
+
+  va_start (arg, format);
+  done = __vfscanf_internal (fp, format, arg, mode_flags);
+  va_end (arg);
+
+  return done;
+}
+strong_alias (___ieee128_isoc99_fscanf, __isoc99_fscanfieee128)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_fwscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_fwscanf.c
new file mode 100644
index 0000000000..d56ecfbaf2
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_fwscanf.c
@@ -0,0 +1,35 @@
+/* Wrapper for __isoc99_fwscanf.  IEEE128 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stdarg.h>
+#include <libioP.h>
+
+extern int
+___ieee128_isoc99_fwscanf (FILE *fp, const wchar_t *format, ...)
+{
+  va_list ap;
+  int done;
+  int mode_flags = SCANF_ISOC99_A | SCANF_LDBL_USES_FLOAT128;
+
+  va_start (ap, format);
+  done = __vfwscanf_internal (fp, format, ap, mode_flags);
+  va_end (ap);
+
+  return done;
+}
+strong_alias (___ieee128_isoc99_fwscanf, __isoc99_fwscanfieee128)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_scanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_scanf.c
new file mode 100644
index 0000000000..5b643fb108
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_scanf.c
@@ -0,0 +1,35 @@
+/* Wrapper for __isoc99_scanf.  IEEE128 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stdarg.h>
+#include <libio/libioP.h>
+
+extern int
+___ieee128_isoc99_scanf (const char *format, ...)
+{
+  va_list arg;
+  int done;
+  int mode_flags = SCANF_ISOC99_A | SCANF_LDBL_USES_FLOAT128;
+
+  va_start (arg, format);
+  done = __vfscanf_internal (stdin, format, arg, mode_flags);
+  va_end (arg);
+
+  return done;
+}
+strong_alias (___ieee128_isoc99_scanf, __isoc99_scanfieee128)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_sscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_sscanf.c
new file mode 100644
index 0000000000..480357ccd5
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_sscanf.c
@@ -0,0 +1,39 @@
+/* Wrapper for __isoc99_sscanf.  IEEE128 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stdarg.h>
+#include <strfile.h>
+#include <libioP.h>
+
+extern int
+___ieee128_isoc99_sscanf (const char *string, const char *format, ...)
+{
+  va_list arg;
+  int done;
+  int mode_flags = SCANF_ISOC99_A | SCANF_LDBL_USES_FLOAT128;
+
+  _IO_strfile sf;
+  FILE *fp = _IO_strfile_read (&sf, string);
+
+  va_start (arg, format);
+  done = __vfscanf_internal (fp, format, arg, mode_flags);
+  va_end (arg);
+
+  return done;
+}
+strong_alias (___ieee128_isoc99_sscanf, __isoc99_sscanfieee128)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_swscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_swscanf.c
new file mode 100644
index 0000000000..e18779a986
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_swscanf.c
@@ -0,0 +1,40 @@
+/* Wrapper for __isoc99_swscanf.  IEEE128 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stdarg.h>
+#include <strfile.h>
+#include <libioP.h>
+
+extern int
+___ieee128_isoc99_swscanf (const wchar_t *string, const wchar_t *format, ...)
+{
+  va_list ap;
+  int done;
+  int mode_flags = SCANF_ISOC99_A | SCANF_LDBL_USES_FLOAT128;
+
+  _IO_strfile sf;
+  struct _IO_wide_data wd;
+  FILE *fp = _IO_strfile_readw (&sf, &wd, string);
+
+  va_start (ap, format);
+  done = __vfwscanf_internal (fp, format, ap, mode_flags);
+  va_end (ap);
+
+  return done;
+}
+strong_alias (___ieee128_isoc99_swscanf, __isoc99_swscanfieee128)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vfscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vfscanf.c
new file mode 100644
index 0000000000..2d131f7fee
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vfscanf.c
@@ -0,0 +1,27 @@
+/* Wrapper for __isoc99_vfscanf.  IEEE128 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <libio/libioP.h>
+
+extern int
+___ieee128_isoc99_vfscanf (FILE *fp, const char *format, va_list ap)
+{
+  int mode_flags = SCANF_ISOC99_A | SCANF_LDBL_USES_FLOAT128;
+  return __vfscanf_internal (fp, format, ap, mode_flags);
+}
+strong_alias (___ieee128_isoc99_vfscanf, __isoc99_vfscanfieee128)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vfwscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vfwscanf.c
new file mode 100644
index 0000000000..a281ecc451
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vfwscanf.c
@@ -0,0 +1,27 @@
+/* Wrapper for __isoc99_vfwscanf.  IEEE128 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <libioP.h>
+
+extern int
+___ieee128_isoc99_vfwscanf (FILE *fp, const wchar_t *format, va_list ap)
+{
+  int mode_flags = SCANF_ISOC99_A | SCANF_LDBL_USES_FLOAT128;
+  return __vfwscanf_internal (fp, format, ap, mode_flags);
+}
+strong_alias (___ieee128_isoc99_vfwscanf, __isoc99_vfwscanfieee128)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vscanf.c
new file mode 100644
index 0000000000..6ec60d5dc0
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vscanf.c
@@ -0,0 +1,27 @@
+/* Wrapper for __isoc99_vscanf.  IEEE128 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <libio/libioP.h>
+
+extern int
+___ieee128_isoc99_vscanf (const char *format, va_list ap)
+{
+  int mode_flags = SCANF_ISOC99_A | SCANF_LDBL_USES_FLOAT128;
+  return __vfscanf_internal (stdin, format, ap, mode_flags);
+}
+strong_alias (___ieee128_isoc99_vscanf, __isoc99_vscanfieee128)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vsscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vsscanf.c
new file mode 100644
index 0000000000..599e86820d
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vsscanf.c
@@ -0,0 +1,30 @@
+/* Wrapper for __isoc99_vsscanf.  IEEE128 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <strfile.h>
+#include <libioP.h>
+
+extern int
+___ieee128_isoc99_vsscanf (const char *string, const char *format, va_list ap)
+{
+  _IO_strfile sf;
+  FILE *fp = _IO_strfile_read (&sf, string);
+  int mode_flags = SCANF_ISOC99_A | SCANF_LDBL_USES_FLOAT128;
+  return __vfscanf_internal (fp, format, ap, mode_flags);
+}
+strong_alias (___ieee128_isoc99_vsscanf, __isoc99_vsscanfieee128)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vswscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vswscanf.c
new file mode 100644
index 0000000000..3a28616c26
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vswscanf.c
@@ -0,0 +1,32 @@
+/* Wrapper for __isoc99_vswscanf.  IEEE128 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <libioP.h>
+#include <wchar.h>
+#include <strfile.h>
+
+extern int
+___ieee128_isoc99_vswscanf (wchar_t *string, const wchar_t *format, va_list ap)
+{
+  _IO_strfile sf;
+  struct _IO_wide_data wd;
+  FILE *fp = _IO_strfile_readw (&sf, &wd, string);
+  int mode_flags = SCANF_ISOC99_A | SCANF_LDBL_USES_FLOAT128;
+  return __vfwscanf_internal (fp, format, ap, mode_flags);
+}
+strong_alias (___ieee128_isoc99_vswscanf, __isoc99_vswscanfieee128)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vwscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vwscanf.c
new file mode 100644
index 0000000000..b9bd4a78f0
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_vwscanf.c
@@ -0,0 +1,27 @@
+/* Wrapper for __isoc99_vwscanf.  IEEE128 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <libioP.h>
+
+extern int
+___ieee128_isoc99_vwscanf (const wchar_t *format, va_list ap)
+{
+  int mode_flags = SCANF_ISOC99_A | SCANF_LDBL_USES_FLOAT128;
+  return __vfwscanf_internal (stdin, format, ap, mode_flags);
+}
+strong_alias (___ieee128_isoc99_vwscanf, __isoc99_vwscanfieee128)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_wscanf.c b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_wscanf.c
new file mode 100644
index 0000000000..e78b4a3143
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/ieee128-isoc99_wscanf.c
@@ -0,0 +1,35 @@
+/* Wrapper for __isoc99_wscanf.  IEEE128 version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stdarg.h>
+#include <libioP.h>
+
+extern int
+___ieee128_isoc99_wscanf (const wchar_t *format, ...)
+{
+  va_list ap;
+  int done;
+  int mode_flags = SCANF_ISOC99_A | SCANF_LDBL_USES_FLOAT128;
+
+  va_start (ap, format);
+  done = __vfwscanf_internal (stdin, format, ap, mode_flags);
+  va_end (ap);
+
+  return done;
+}
+strong_alias (___ieee128_isoc99_wscanf, __isoc99_wscanfieee128)
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ibm128.c b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ibm128.c
new file mode 100644
index 0000000000..70688ac2bb
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ibm128.c
@@ -0,0 +1,13 @@
+#undef _GNU_SOURCE
+/* The following macro definitions are a hack.  They word around disabling
+   the GNU extension while still using a few internal headers.  */
+#define u_char unsigned char
+#define u_short unsigned short
+#define u_int unsigned int
+#define u_long unsigned long
+#include <libio/stdio.h>
+#include <stdlib/stdlib.h>
+#include <string/string.h>
+#include <wcsmbs/wchar.h>
+
+#include <test-isoc99-scanf-ldbl-compat.c>
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ieee128.c b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ieee128.c
new file mode 100644
index 0000000000..70688ac2bb
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ieee128.c
@@ -0,0 +1,13 @@
+#undef _GNU_SOURCE
+/* The following macro definitions are a hack.  They word around disabling
+   the GNU extension while still using a few internal headers.  */
+#define u_char unsigned char
+#define u_short unsigned short
+#define u_int unsigned int
+#define u_long unsigned long
+#include <libio/stdio.h>
+#include <stdlib/stdlib.h>
+#include <string/string.h>
+#include <wcsmbs/wchar.h>
+
+#include <test-isoc99-scanf-ldbl-compat.c>
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ldbl-compat-template.c b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ldbl-compat-template.c
new file mode 100644
index 0000000000..ffc7ca2aaa
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ldbl-compat-template.c
@@ -0,0 +1,119 @@
+/* Test for the long double variants of __isoc99_*scanf functions.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <wchar.h>
+
+#include <support/check.h>
+
+#define CLEAR_VARGS							\
+  va_start (args, format);						\
+  ldptr = va_arg (args, long double *);					\
+  fptr = va_arg (args, float *);					\
+  *ldptr = 0;								\
+  *fptr = 0;								\
+  va_end (args);
+
+#define CHECK_VARGS							\
+  va_start (args, format);						\
+  ldptr = va_arg (args, long double *);					\
+  fptr = va_arg (args, float *);					\
+  va_end (args);							\
+  if (*ldptr == -1 && *fptr == -2)					\
+    printf ("OK");							\
+  else									\
+    printf ("ERROR (%Lf %f)", *ldptr, *fptr);				\
+  printf ("\n");
+
+#define CLEAR_VALUE							\
+  ld = 0;								\
+  f = 0;
+
+#define CHECK_VALUE							\
+  if (ld == -1 && f == -2)						\
+    printf ("OK");							\
+  else									\
+    printf ("ERROR (%Lf %f)", ld, f);					\
+  printf ("\n");
+
+static void
+do_test_call (FILE *stream, CHAR *string, const CHAR *format, ...)
+{
+  float *fptr;
+  float f;
+  long double *ldptr;
+  long double ld;
+  va_list args;
+
+  CLEAR_VALUE
+  printf ("fscanf: ");
+  FSCANF (stream, format, &ld, &f);
+  CHECK_VALUE
+
+  CLEAR_VALUE
+  printf ("scanf: ");
+  SCANF (format, &ld, &f);
+  CHECK_VALUE
+
+  CLEAR_VALUE
+  printf ("sscanf: ");
+  SSCANF (string, format, &ld, &f);
+  CHECK_VALUE
+
+  CLEAR_VARGS
+  printf ("vfscanf: ");
+  va_start (args, format);
+  VFSCANF (stream, format, args);
+  va_end (args);
+  CHECK_VARGS
+
+  CLEAR_VARGS
+  printf ("vscanf: ");
+  va_start (args, format);
+  VSCANF (format, args);
+  va_end (args);
+  CHECK_VARGS
+
+  CLEAR_VARGS
+  printf ("vsscanf: ");
+  va_start (args, format);
+  VSSCANF (string, format, args);
+  va_end (args);
+  CHECK_VARGS
+}
+
+static int
+do_test (void)
+{
+  CHAR string[256];
+  float f;
+  long double ld;
+
+  /* Scan floating-point value with '%as'.  */
+  STRCPY (string,
+	  L ("-0x1.0p+0 -0x2.0p+0\n")
+	  L ("-0x1.0p+0 -0x2.0p+0\n") );
+  do_test_call (stdin, string, L("%La %as"), &ld, &f);
+
+  return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ldbl-compat.c b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ldbl-compat.c
new file mode 100644
index 0000000000..739b6bb479
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ldbl-compat.c
@@ -0,0 +1,10 @@
+#define CHAR char
+#define L(x) x
+#define FSCANF fscanf
+#define SSCANF sscanf
+#define SCANF scanf
+#define VFSCANF vfscanf
+#define VSSCANF vsscanf
+#define VSCANF vscanf
+#define STRCPY strcpy
+#include <test-isoc99-scanf-ldbl-compat-template.c>
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ldbl-compat.sh b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ldbl-compat.sh
new file mode 100644
index 0000000000..fc08beddc5
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-scanf-ldbl-compat.sh
@@ -0,0 +1,53 @@
+#!/bin/sh
+# Testing of __isoc99_*scanf.  IEEE binary128 for powerpc64le version.
+# Copyright (C) 2018 Free Software Foundation, Inc.
+# This file is part of the GNU C Library.
+
+# The GNU C Library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+
+# The GNU C Library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+
+# You should have received a copy of the GNU Lesser General Public
+# License along with the GNU C Library; if not, see
+# <http://www.gnu.org/licenses/>.
+
+set -e
+
+test_program=$1; shift
+test_program_prefix=$1; shift
+test_program_output=$1; shift
+
+status=0
+
+cat <<'EOF' |
+-0x1.0p+0 -0x2.0p+0
+-0x1.0p+0 -0x2.0p+0
+-0x1.0p+0 -0x2.0p+0
+-0x1.0p+0 -0x2.0p+0
+EOF
+${test_program_prefix} \
+  ${test_program} \
+  - \
+  > ${test_program_output} || status=1
+
+cat <<'EOF' |
+fscanf: OK
+scanf: OK
+sscanf: OK
+vfscanf: OK
+vscanf: OK
+vsscanf: OK
+EOF
+cmp - ${test_program_output} > /dev/null 2>&1 ||
+{
+  status=1
+  echo "*** output comparison failed"
+}
+
+exit $status
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-wscanf-ibm128.c b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-wscanf-ibm128.c
new file mode 100644
index 0000000000..6be29624d9
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-wscanf-ibm128.c
@@ -0,0 +1,13 @@
+#undef _GNU_SOURCE
+/* The following macro definitions are a hack.  They word around disabling
+   the GNU extension while still using a few internal headers.  */
+#define u_char unsigned char
+#define u_short unsigned short
+#define u_int unsigned int
+#define u_long unsigned long
+#include <libio/stdio.h>
+#include <stdlib/stdlib.h>
+#include <string/string.h>
+#include <wcsmbs/wchar.h>
+
+#include <test-isoc99-wscanf-ldbl-compat.c>
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-wscanf-ieee128.c b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-wscanf-ieee128.c
new file mode 100644
index 0000000000..6be29624d9
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-wscanf-ieee128.c
@@ -0,0 +1,13 @@
+#undef _GNU_SOURCE
+/* The following macro definitions are a hack.  They word around disabling
+   the GNU extension while still using a few internal headers.  */
+#define u_char unsigned char
+#define u_short unsigned short
+#define u_int unsigned int
+#define u_long unsigned long
+#include <libio/stdio.h>
+#include <stdlib/stdlib.h>
+#include <string/string.h>
+#include <wcsmbs/wchar.h>
+
+#include <test-isoc99-wscanf-ldbl-compat.c>
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-wscanf-ldbl-compat.c b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-wscanf-ldbl-compat.c
new file mode 100644
index 0000000000..3ad29645f6
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/test-isoc99-wscanf-ldbl-compat.c
@@ -0,0 +1,10 @@
+#define CHAR wchar_t
+#define L(x) L##x
+#define FSCANF fwscanf
+#define SSCANF swscanf
+#define SCANF wscanf
+#define VFSCANF vfwscanf
+#define VSSCANF vswscanf
+#define VSCANF vwscanf
+#define STRCPY wcscpy
+#include <test-isoc99-scanf-ldbl-compat-template.c>
diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/test-scanf-ldbl-compat-template.c b/sysdeps/ieee754/ldbl-128ibm-compat/test-scanf-ldbl-compat-template.c
index 4590e9da96..aea4f0d358 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/test-scanf-ldbl-compat-template.c
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/test-scanf-ldbl-compat-template.c
@@ -53,8 +53,10 @@ static void
 do_test_call (FILE *stream, CHAR *string, const CHAR *format, ...)
 {
   long double value;
+#if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
   long double *ld;
   va_list args;
+#endif
 
   CLEAR_VALUE
   printf ("fscanf: ");
@@ -71,6 +73,7 @@ do_test_call (FILE *stream, CHAR *string, const CHAR *format, ...)
   SSCANF (string, format, &value);
   CHECK_VALUE
 
+#if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
   CLEAR
   printf ("vfscanf: ");
   va_start (args, format);
@@ -91,6 +94,7 @@ do_test_call (FILE *stream, CHAR *string, const CHAR *format, ...)
   VSSCANF (string, format, args);
   va_end (args);
   CHECK
+#endif
 }
 
 static int
