updated gnulib

14 files changed, 379 insertions, 91 deletions

diff --git a/gl/Makefile.am b/gl/Makefile.am
index 5f2c06469f..4170af2620 100644
--- a/gl/Makefile.am
+++ b/gl/Makefile.am
@@ -755,6 +755,10 @@ math.h: math.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H) $(
 	      -e 's/@''GNULIB_HYPOT''@/$(GNULIB_HYPOT)/g' \
 	      -e 's/@''GNULIB_HYPOTF''@/$(GNULIB_HYPOTF)/g' \
 	      -e 's/@''GNULIB_HYPOTL''@/$(GNULIB_HYPOTL)/g' \
+	      < $(srcdir)/math.in.h | \
+	  sed -e 's/@''GNULIB_ILOGB''@/$(GNULIB_ILOGB)/g' \
+	      -e 's/@''GNULIB_ILOGBF''@/$(GNULIB_ILOGBF)/g' \
+	      -e 's/@''GNULIB_ILOGBL''@/$(GNULIB_ILOGBL)/g' \
 	      -e 's/@''GNULIB_ISFINITE''@/$(GNULIB_ISFINITE)/g' \
 	      -e 's/@''GNULIB_ISINF''@/$(GNULIB_ISINF)/g' \
 	      -e 's/@''GNULIB_ISNAN''@/$(GNULIB_ISNAN)/g' \
@@ -763,10 +767,10 @@ math.h: math.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H) $(
 	      -e 's/@''GNULIB_ISNANL''@/$(GNULIB_ISNANL)/g' \
 	      -e 's/@''GNULIB_LDEXPF''@/$(GNULIB_LDEXPF)/g' \
 	      -e 's/@''GNULIB_LDEXPL''@/$(GNULIB_LDEXPL)/g' \
-	      -e 's/@''GNULIB_LOGB''@/$(GNULIB_LOGB)/g' \
 	      -e 's/@''GNULIB_LOG''@/$(GNULIB_LOG)/g' \
 	      -e 's/@''GNULIB_LOGF''@/$(GNULIB_LOGF)/g' \
 	      -e 's/@''GNULIB_LOGL''@/$(GNULIB_LOGL)/g' \
+	      -e 's/@''GNULIB_LOG10''@/$(GNULIB_LOG10)/g' \
 	      -e 's/@''GNULIB_LOG10F''@/$(GNULIB_LOG10F)/g' \
 	      -e 's/@''GNULIB_LOG10L''@/$(GNULIB_LOG10L)/g' \
 	      -e 's/@''GNULIB_LOG1P''@/$(GNULIB_LOG1P)/g' \
@@ -775,6 +779,9 @@ math.h: math.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H) $(
 	      -e 's/@''GNULIB_LOG2''@/$(GNULIB_LOG2)/g' \
 	      -e 's/@''GNULIB_LOG2F''@/$(GNULIB_LOG2F)/g' \
 	      -e 's/@''GNULIB_LOG2L''@/$(GNULIB_LOG2L)/g' \
+	      -e 's/@''GNULIB_LOGB''@/$(GNULIB_LOGB)/g' \
+	      -e 's/@''GNULIB_LOGBF''@/$(GNULIB_LOGBF)/g' \
+	      -e 's/@''GNULIB_LOGBL''@/$(GNULIB_LOGBL)/g' \
 	      -e 's/@''GNULIB_MODF''@/$(GNULIB_MODF)/g' \
 	      -e 's/@''GNULIB_MODFF''@/$(GNULIB_MODFF)/g' \
 	      -e 's/@''GNULIB_MODFL''@/$(GNULIB_MODFL)/g' \
@@ -800,7 +807,7 @@ math.h: math.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H) $(
 	      -e 's/@''GNULIB_TRUNC''@/$(GNULIB_TRUNC)/g' \
 	      -e 's/@''GNULIB_TRUNCF''@/$(GNULIB_TRUNCF)/g' \
 	      -e 's/@''GNULIB_TRUNCL''@/$(GNULIB_TRUNCL)/g' \
-	      < $(srcdir)/math.in.h | \
+	  | \
 	  sed -e 's|@''HAVE_ACOSF''@|$(HAVE_ACOSF)|g' \
 	      -e 's|@''HAVE_ACOSL''@|$(HAVE_ACOSL)|g' \
 	      -e 's|@''HAVE_ASINF''@|$(HAVE_ASINF)|g' \
@@ -830,6 +837,9 @@ math.h: math.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H) $(
 	      -e 's|@''HAVE_FREXPF''@|$(HAVE_FREXPF)|g' \
 	      -e 's|@''HAVE_HYPOTF''@|$(HAVE_HYPOTF)|g' \
 	      -e 's|@''HAVE_HYPOTL''@|$(HAVE_HYPOTL)|g' \
+	      -e 's|@''HAVE_ILOGB''@|$(HAVE_ILOGB)|g' \
+	      -e 's|@''HAVE_ILOGBF''@|$(HAVE_ILOGBF)|g' \
+	      -e 's|@''HAVE_ILOGBL''@|$(HAVE_ILOGBL)|g' \
 	      -e 's|@''HAVE_ISNANF''@|$(HAVE_ISNANF)|g' \
 	      -e 's|@''HAVE_ISNAND''@|$(HAVE_ISNAND)|g' \
 	      -e 's|@''HAVE_ISNANL''@|$(HAVE_ISNANL)|g' \
@@ -841,6 +851,8 @@ math.h: math.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H) $(
 	      -e 's|@''HAVE_LOG1P''@|$(HAVE_LOG1P)|g' \
 	      -e 's|@''HAVE_LOG1PF''@|$(HAVE_LOG1PF)|g' \
 	      -e 's|@''HAVE_LOG1PL''@|$(HAVE_LOG1PL)|g' \
+	      -e 's|@''HAVE_LOGBF''@|$(HAVE_LOGBF)|g' \
+	      -e 's|@''HAVE_LOGBL''@|$(HAVE_LOGBL)|g' \
 	      -e 's|@''HAVE_MODFF''@|$(HAVE_MODFF)|g' \
 	      -e 's|@''HAVE_MODFL''@|$(HAVE_MODFL)|g' \
 	      -e 's|@''HAVE_POWF''@|$(HAVE_POWF)|g' \
@@ -874,12 +886,12 @@ math.h: math.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H) $(
 	      -e 's|@''HAVE_DECL_FLOORL''@|$(HAVE_DECL_FLOORL)|g' \
 	      -e 's|@''HAVE_DECL_FREXPL''@|$(HAVE_DECL_FREXPL)|g' \
 	      -e 's|@''HAVE_DECL_LDEXPL''@|$(HAVE_DECL_LDEXPL)|g' \
-	      -e 's|@''HAVE_DECL_LOGB''@|$(HAVE_DECL_LOGB)|g' \
 	      -e 's|@''HAVE_DECL_LOGL''@|$(HAVE_DECL_LOGL)|g' \
 	      -e 's|@''HAVE_DECL_LOG10L''@|$(HAVE_DECL_LOG10L)|g' \
 	      -e 's|@''HAVE_DECL_LOG2''@|$(HAVE_DECL_LOG2)|g' \
 	      -e 's|@''HAVE_DECL_LOG2F''@|$(HAVE_DECL_LOG2F)|g' \
 	      -e 's|@''HAVE_DECL_LOG2L''@|$(HAVE_DECL_LOG2L)|g' \
+	      -e 's|@''HAVE_DECL_LOGB''@|$(HAVE_DECL_LOGB)|g' \
 	      -e 's|@''HAVE_DECL_REMAINDER''@|$(HAVE_DECL_REMAINDER)|g' \
 	      -e 's|@''HAVE_DECL_REMAINDERL''@|$(HAVE_DECL_REMAINDERL)|g' \
 	      -e 's|@''HAVE_DECL_RINTF''@|$(HAVE_DECL_RINTF)|g' \
@@ -919,6 +931,8 @@ math.h: math.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H) $(
 	      -e 's|@''REPLACE_HYPOT''@|$(REPLACE_HYPOT)|g' \
 	      -e 's|@''REPLACE_HYPOTF''@|$(REPLACE_HYPOTF)|g' \
 	      -e 's|@''REPLACE_HYPOTL''@|$(REPLACE_HYPOTL)|g' \
+	      -e 's|@''REPLACE_ILOGB''@|$(REPLACE_ILOGB)|g' \
+	      -e 's|@''REPLACE_ILOGBF''@|$(REPLACE_ILOGBF)|g' \
 	      -e 's|@''REPLACE_ISFINITE''@|$(REPLACE_ISFINITE)|g' \
 	      -e 's|@''REPLACE_ISINF''@|$(REPLACE_ISINF)|g' \
 	      -e 's|@''REPLACE_ISNAN''@|$(REPLACE_ISNAN)|g' \
@@ -927,12 +941,18 @@ math.h: math.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H) $(
 	      -e 's|@''REPLACE_LOG''@|$(REPLACE_LOG)|g' \
 	      -e 's|@''REPLACE_LOGF''@|$(REPLACE_LOGF)|g' \
 	      -e 's|@''REPLACE_LOGL''@|$(REPLACE_LOGL)|g' \
+	      -e 's|@''REPLACE_LOG10''@|$(REPLACE_LOG10)|g' \
+	      -e 's|@''REPLACE_LOG10F''@|$(REPLACE_LOG10F)|g' \
+	      -e 's|@''REPLACE_LOG10L''@|$(REPLACE_LOG10L)|g' \
 	      -e 's|@''REPLACE_LOG1P''@|$(REPLACE_LOG1P)|g' \
 	      -e 's|@''REPLACE_LOG1PF''@|$(REPLACE_LOG1PF)|g' \
 	      -e 's|@''REPLACE_LOG1PL''@|$(REPLACE_LOG1PL)|g' \
 	      -e 's|@''REPLACE_LOG2''@|$(REPLACE_LOG2)|g' \
 	      -e 's|@''REPLACE_LOG2F''@|$(REPLACE_LOG2F)|g' \
 	      -e 's|@''REPLACE_LOG2L''@|$(REPLACE_LOG2L)|g' \
+	      -e 's|@''REPLACE_LOGB''@|$(REPLACE_LOGB)|g' \
+	      -e 's|@''REPLACE_LOGBF''@|$(REPLACE_LOGBF)|g' \
+	      -e 's|@''REPLACE_LOGBL''@|$(REPLACE_LOGBL)|g' \
 	      -e 's|@''REPLACE_MODF''@|$(REPLACE_MODF)|g' \
 	      -e 's|@''REPLACE_MODFF''@|$(REPLACE_MODFF)|g' \
 	      -e 's|@''REPLACE_MODFL''@|$(REPLACE_MODFL)|g' \
@@ -1588,7 +1608,6 @@ stdio.h: stdio.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H)
 	      -e 's/@''GNULIB_GETCHAR''@/$(GNULIB_GETCHAR)/g' \
 	      -e 's/@''GNULIB_GETDELIM''@/$(GNULIB_GETDELIM)/g' \
 	      -e 's/@''GNULIB_GETLINE''@/$(GNULIB_GETLINE)/g' \
-	      -e 's/@''GNULIB_GETS''@/$(GNULIB_GETS)/g' \
 	      -e 's/@''GNULIB_OBSTACK_PRINTF''@/$(GNULIB_OBSTACK_PRINTF)/g' \
 	      -e 's/@''GNULIB_OBSTACK_PRINTF_POSIX''@/$(GNULIB_OBSTACK_PRINTF_POSIX)/g' \
 	      -e 's/@''GNULIB_PCLOSE''@/$(GNULIB_PCLOSE)/g' \
diff --git a/gl/dirent.in.h b/gl/dirent.in.h
index 808b360856..cdbc5fd4fd 100644
--- a/gl/dirent.in.h
+++ b/gl/dirent.in.h
@@ -55,6 +55,14 @@ typedef struct gl_directory DIR;
 # endif
 #endif
 
+/* The __attribute__ feature is available in gcc versions 2.5 and later.
+   The attribute __pure__ was added in gcc 2.96.  */
+#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
+# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
+#else
+# define _GL_ATTRIBUTE_PURE /* empty */
+#endif
+
 /* The definitions of _GL_FUNCDECL_RPL etc. are copied here.  */
 
 /* The definition of _GL_ARG_NONNULL is copied here.  */
@@ -229,6 +237,7 @@ _GL_WARN_ON_USE (scandir, "scandir is unportable - "
 # if !@HAVE_ALPHASORT@
 _GL_FUNCDECL_SYS (alphasort, int,
                   (const struct dirent **, const struct dirent **)
+                  _GL_ATTRIBUTE_PURE
                   _GL_ARG_NONNULL ((1, 2)));
 # endif
 /* Need to cast, because on glibc systems, the parameters are
diff --git a/gl/m4/math_h.m4 b/gl/m4/math_h.m4
index ff1654ec7f..90d248aecc 100644
--- a/gl/m4/math_h.m4
+++ b/gl/m4/math_h.m4
@@ -1,4 +1,4 @@
-# math_h.m4 serial 104
+# math_h.m4 serial 113
 dnl Copyright (C) 2007-2012 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -44,8 +44,10 @@ AC_DEFUN([gl_MATH_H],
      expf expl exp2 exp2f exp2l expm1 expm1f expm1l
      fabsf fabsl floorf floorl fma fmaf fmal
      fmod fmodf fmodl frexpf frexpl hypotf hypotl
+     ilogb ilogbf ilogbl
      ldexpf ldexpl
-     logb log logf logl log10f log10l log1p log1pf log1pl log2 log2f log2l
+     log logf logl log10 log10f log10l log1p log1pf log1pl log2 log2f log2l
+     logb logbf logbl
      modf modff modfl powf
      remainder remainderf remainderl
      rint rintf rintl round roundf roundl sinf sinl sinhf sqrtf sqrtl
@@ -107,6 +109,9 @@ AC_DEFUN([gl_MATH_H_DEFAULTS],
   GNULIB_HYPOT=0;      AC_SUBST([GNULIB_HYPOT])
   GNULIB_HYPOTF=0;     AC_SUBST([GNULIB_HYPOTF])
   GNULIB_HYPOTL=0;     AC_SUBST([GNULIB_HYPOTL])
+  GNULIB_ILOGB=0;      AC_SUBST([GNULIB_ILOGB])
+  GNULIB_ILOGBF=0;     AC_SUBST([GNULIB_ILOGBF])
+  GNULIB_ILOGBL=0;     AC_SUBST([GNULIB_ILOGBL])
   GNULIB_ISFINITE=0;   AC_SUBST([GNULIB_ISFINITE])
   GNULIB_ISINF=0;      AC_SUBST([GNULIB_ISINF])
   GNULIB_ISNAN=0;      AC_SUBST([GNULIB_ISNAN])
@@ -115,10 +120,10 @@ AC_DEFUN([gl_MATH_H_DEFAULTS],
   GNULIB_ISNANL=0;     AC_SUBST([GNULIB_ISNANL])
   GNULIB_LDEXPF=0;     AC_SUBST([GNULIB_LDEXPF])
   GNULIB_LDEXPL=0;     AC_SUBST([GNULIB_LDEXPL])
-  GNULIB_LOGB=0;       AC_SUBST([GNULIB_LOGB])
   GNULIB_LOG=0;        AC_SUBST([GNULIB_LOG])
   GNULIB_LOGF=0;       AC_SUBST([GNULIB_LOGF])
   GNULIB_LOGL=0;       AC_SUBST([GNULIB_LOGL])
+  GNULIB_LOG10=0;      AC_SUBST([GNULIB_LOG10])
   GNULIB_LOG10F=0;     AC_SUBST([GNULIB_LOG10F])
   GNULIB_LOG10L=0;     AC_SUBST([GNULIB_LOG10L])
   GNULIB_LOG1P=0;      AC_SUBST([GNULIB_LOG1P])
@@ -127,6 +132,9 @@ AC_DEFUN([gl_MATH_H_DEFAULTS],
   GNULIB_LOG2=0;       AC_SUBST([GNULIB_LOG2])
   GNULIB_LOG2F=0;      AC_SUBST([GNULIB_LOG2F])
   GNULIB_LOG2L=0;      AC_SUBST([GNULIB_LOG2L])
+  GNULIB_LOGB=0;       AC_SUBST([GNULIB_LOGB])
+  GNULIB_LOGBF=0;      AC_SUBST([GNULIB_LOGBF])
+  GNULIB_LOGBL=0;      AC_SUBST([GNULIB_LOGBL])
   GNULIB_MODF=0;       AC_SUBST([GNULIB_MODF])
   GNULIB_MODFF=0;      AC_SUBST([GNULIB_MODFF])
   GNULIB_MODFL=0;      AC_SUBST([GNULIB_MODFL])
@@ -182,6 +190,9 @@ AC_DEFUN([gl_MATH_H_DEFAULTS],
   HAVE_FREXPF=1;               AC_SUBST([HAVE_FREXPF])
   HAVE_HYPOTF=1;               AC_SUBST([HAVE_HYPOTF])
   HAVE_HYPOTL=1;               AC_SUBST([HAVE_HYPOTL])
+  HAVE_ILOGB=1;                AC_SUBST([HAVE_ILOGB])
+  HAVE_ILOGBF=1;               AC_SUBST([HAVE_ILOGBF])
+  HAVE_ILOGBL=1;               AC_SUBST([HAVE_ILOGBL])
   HAVE_ISNANF=1;               AC_SUBST([HAVE_ISNANF])
   HAVE_ISNAND=1;               AC_SUBST([HAVE_ISNAND])
   HAVE_ISNANL=1;               AC_SUBST([HAVE_ISNANL])
@@ -193,6 +204,8 @@ AC_DEFUN([gl_MATH_H_DEFAULTS],
   HAVE_LOG1P=1;                AC_SUBST([HAVE_LOG1P])
   HAVE_LOG1PF=1;               AC_SUBST([HAVE_LOG1PF])
   HAVE_LOG1PL=1;               AC_SUBST([HAVE_LOG1PL])
+  HAVE_LOGBF=1;                AC_SUBST([HAVE_LOGBF])
+  HAVE_LOGBL=1;                AC_SUBST([HAVE_LOGBL])
   HAVE_MODFF=1;                AC_SUBST([HAVE_MODFF])
   HAVE_MODFL=1;                AC_SUBST([HAVE_MODFL])
   HAVE_POWF=1;                 AC_SUBST([HAVE_POWF])
@@ -226,12 +239,12 @@ AC_DEFUN([gl_MATH_H_DEFAULTS],
   HAVE_DECL_FLOORL=1;          AC_SUBST([HAVE_DECL_FLOORL])
   HAVE_DECL_FREXPL=1;          AC_SUBST([HAVE_DECL_FREXPL])
   HAVE_DECL_LDEXPL=1;          AC_SUBST([HAVE_DECL_LDEXPL])
-  HAVE_DECL_LOGB=1;            AC_SUBST([HAVE_DECL_LOGB])
   HAVE_DECL_LOGL=1;            AC_SUBST([HAVE_DECL_LOGL])
   HAVE_DECL_LOG10L=1;          AC_SUBST([HAVE_DECL_LOG10L])
   HAVE_DECL_LOG2=1;            AC_SUBST([HAVE_DECL_LOG2])
   HAVE_DECL_LOG2F=1;           AC_SUBST([HAVE_DECL_LOG2F])
   HAVE_DECL_LOG2L=1;           AC_SUBST([HAVE_DECL_LOG2L])
+  HAVE_DECL_LOGB=1;            AC_SUBST([HAVE_DECL_LOGB])
   HAVE_DECL_REMAINDER=1;       AC_SUBST([HAVE_DECL_REMAINDER])
   HAVE_DECL_REMAINDERL=1;      AC_SUBST([HAVE_DECL_REMAINDERL])
   HAVE_DECL_RINTF=1;           AC_SUBST([HAVE_DECL_RINTF])
@@ -270,6 +283,8 @@ AC_DEFUN([gl_MATH_H_DEFAULTS],
   REPLACE_HYPOT=0;             AC_SUBST([REPLACE_HYPOT])
   REPLACE_HYPOTF=0;            AC_SUBST([REPLACE_HYPOTF])
   REPLACE_HYPOTL=0;            AC_SUBST([REPLACE_HYPOTL])
+  REPLACE_ILOGB=0;             AC_SUBST([REPLACE_ILOGB])
+  REPLACE_ILOGBF=0;            AC_SUBST([REPLACE_ILOGBF])
   REPLACE_ISFINITE=0;          AC_SUBST([REPLACE_ISFINITE])
   REPLACE_ISINF=0;             AC_SUBST([REPLACE_ISINF])
   REPLACE_ISNAN=0;             AC_SUBST([REPLACE_ISNAN])
@@ -277,12 +292,18 @@ AC_DEFUN([gl_MATH_H_DEFAULTS],
   REPLACE_LOG=0;               AC_SUBST([REPLACE_LOG])
   REPLACE_LOGF=0;              AC_SUBST([REPLACE_LOGF])
   REPLACE_LOGL=0;              AC_SUBST([REPLACE_LOGL])
+  REPLACE_LOG10=0;             AC_SUBST([REPLACE_LOG10])
+  REPLACE_LOG10F=0;            AC_SUBST([REPLACE_LOG10F])
+  REPLACE_LOG10L=0;            AC_SUBST([REPLACE_LOG10L])
   REPLACE_LOG1P=0;             AC_SUBST([REPLACE_LOG1P])
   REPLACE_LOG1PF=0;            AC_SUBST([REPLACE_LOG1PF])
   REPLACE_LOG1PL=0;            AC_SUBST([REPLACE_LOG1PL])
   REPLACE_LOG2=0;              AC_SUBST([REPLACE_LOG2])
   REPLACE_LOG2F=0;             AC_SUBST([REPLACE_LOG2F])
   REPLACE_LOG2L=0;             AC_SUBST([REPLACE_LOG2L])
+  REPLACE_LOGB=0;              AC_SUBST([REPLACE_LOGB])
+  REPLACE_LOGBF=0;             AC_SUBST([REPLACE_LOGBF])
+  REPLACE_LOGBL=0;             AC_SUBST([REPLACE_LOGBL])
   REPLACE_MODF=0;              AC_SUBST([REPLACE_MODF])
   REPLACE_MODFF=0;             AC_SUBST([REPLACE_MODFF])
   REPLACE_MODFL=0;             AC_SUBST([REPLACE_MODFL])
diff --git a/gl/m4/stdio_h.m4 b/gl/m4/stdio_h.m4
index 1973e8db15..b03393b957 100644
--- a/gl/m4/stdio_h.m4
+++ b/gl/m4/stdio_h.m4
@@ -1,4 +1,4 @@
-# stdio_h.m4 serial 40
+# stdio_h.m4 serial 41
 dnl Copyright (C) 2007-2012 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -18,7 +18,6 @@ AC_DEFUN([gl_STDIO_H],
   GNULIB_GETC=1
   GNULIB_GETCHAR=1
   GNULIB_FGETS=1
-  GNULIB_GETS=1
   GNULIB_FREAD=1
   dnl This ifdef is necessary to avoid an error "missing file lib/stdio-read.c"
   dnl "expected source file, required through AC_LIBSOURCES, not found". It is
@@ -72,10 +71,10 @@ AC_DEFUN([gl_STDIO_H],
 
   dnl Check for declarations of anything we want to poison if the
   dnl corresponding gnulib module is not in use, and which is not
-  dnl guaranteed by C89.
+  dnl guaranteed by both C89 and C11.
   gl_WARN_ON_USE_PREPARE([[#include <stdio.h>
-    ]], [dprintf fpurge fseeko ftello getdelim getline pclose popen renameat
-    snprintf tmpfile vdprintf vsnprintf])
+    ]], [dprintf fpurge fseeko ftello getdelim getline gets pclose popen
+    renameat snprintf tmpfile vdprintf vsnprintf])
 ])
 
 AC_DEFUN([gl_STDIO_MODULE_INDICATOR],
@@ -113,7 +112,6 @@ AC_DEFUN([gl_STDIO_H_DEFAULTS],
   GNULIB_GETCHAR=0;              AC_SUBST([GNULIB_GETCHAR])
   GNULIB_GETDELIM=0;             AC_SUBST([GNULIB_GETDELIM])
   GNULIB_GETLINE=0;              AC_SUBST([GNULIB_GETLINE])
-  GNULIB_GETS=0;                 AC_SUBST([GNULIB_GETS])
   GNULIB_OBSTACK_PRINTF=0;       AC_SUBST([GNULIB_OBSTACK_PRINTF])
   GNULIB_OBSTACK_PRINTF_POSIX=0; AC_SUBST([GNULIB_OBSTACK_PRINTF_POSIX])
   GNULIB_PCLOSE=0;               AC_SUBST([GNULIB_PCLOSE])
diff --git a/gl/m4/warn-on-use.m4 b/gl/m4/warn-on-use.m4
index 03b113cf40..a77802eb91 100644
--- a/gl/m4/warn-on-use.m4
+++ b/gl/m4/warn-on-use.m4
@@ -1,4 +1,4 @@
-# warn-on-use.m4 serial 4
+# warn-on-use.m4 serial 5
 dnl Copyright (C) 2010-2012 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -18,8 +18,8 @@ dnl with or without modifications, as long as this notice is preserved.
 # some systems declare functions in the wrong header, then INCLUDES
 # should do likewise.
 #
-# If you assume C89, then it is generally safe to assume declarations
-# for functions declared in that standard (such as gets) without
+# It is generally safe to assume declarations for functions declared
+# in the intersection of C89 and C11 (such as printf) without
 # needing gl_WARN_ON_USE_PREPARE.
 AC_DEFUN([gl_WARN_ON_USE_PREPARE],
 [
diff --git a/gl/m4/warnings.m4 b/gl/m4/warnings.m4
index 69d05a6700..c14c4801e7 100644
--- a/gl/m4/warnings.m4
+++ b/gl/m4/warnings.m4
@@ -1,4 +1,4 @@
-# warnings.m4 serial 5
+# warnings.m4 serial 6
 dnl Copyright (C) 2008-2012 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -14,24 +14,29 @@ m4_ifdef([AS_VAR_APPEND],
 [m4_define([gl_AS_VAR_APPEND],
 [AS_VAR_SET([$1], [AS_VAR_GET([$1])$2])])])
 
+
 # gl_WARN_ADD(PARAMETER, [VARIABLE = WARN_CFLAGS])
 # ------------------------------------------------
 # Adds parameter to WARN_CFLAGS if the compiler supports it.  For example,
 # gl_WARN_ADD([-Wparentheses]).
+#
+# If VARIABLE is a variable name, AC_SUBST it.
 AC_DEFUN([gl_WARN_ADD],
 dnl FIXME: gl_Warn must be used unquoted until we can assume
 dnl autoconf 2.64 or newer.
-[AS_VAR_PUSHDEF([gl_Warn], [gl_cv_warn_$1])dnl
-AC_CACHE_CHECK([whether compiler handles $1], m4_defn([gl_Warn]), [
-  gl_save_CPPFLAGS="$CPPFLAGS"
-  CPPFLAGS="${CPPFLAGS} $1"
-  AC_PREPROC_IFELSE([AC_LANG_PROGRAM([])],
+[AS_VAR_PUSHDEF([gl_Warn], [gl_cv_warn_[]_AC_LANG_ABBREV[]_$1])dnl
+AS_VAR_PUSHDEF([gl_Flags], [_AC_LANG_PREFIX[]FLAGS])dnl
+AC_CACHE_CHECK([whether _AC_LANG compiler handles $1], m4_defn([gl_Warn]), [
+  gl_save_compiler_FLAGS="$gl_Flags"
+  gl_Flags="$gl_Flags $1"
+  AC_COMPILE_IFELSE([AC_LANG_PROGRAM([])],
                     [AS_VAR_SET(gl_Warn, [yes])],
                     [AS_VAR_SET(gl_Warn, [no])])
-  CPPFLAGS="$gl_save_CPPFLAGS"
+  gl_Flags="$gl_save_compiler_FLAGS"
 ])
 AS_VAR_IF(gl_Warn, [yes],
   [gl_AS_VAR_APPEND(m4_if([$2], [], [[WARN_CFLAGS]], [[$2]]), [" $1"])])
+AS_VAR_POPDEF([gl_Flags])dnl
 AS_VAR_POPDEF([gl_Warn])dnl
 m4_ifval([$2], [AS_LITERAL_IF([$2], [AC_SUBST([$2])], [])])dnl
 ])
diff --git a/gl/math.in.h b/gl/math.in.h
index 4b2ce87ac2..0625777acc 100644
--- a/gl/math.in.h
+++ b/gl/math.in.h
@@ -179,6 +179,29 @@ _NaN ()
 # endif
 #endif
 
+
+/* Ensure FP_ILOGB0 and FP_ILOGBNAN are defined.  */
+#if !(defined FP_ILOGB0 && defined FP_ILOGBNAN)
+# if defined __NetBSD__ || defined __sgi
+  /* NetBSD, IRIX 6.5: match what ilogb() does */
+#  define FP_ILOGB0   (- 2147483647 - 1) /* INT_MIN */
+#  define FP_ILOGBNAN (- 2147483647 - 1) /* INT_MIN */
+# elif defined _AIX
+  /* AIX 5.1: match what ilogb() does in AIX >= 5.2 */
+#  define FP_ILOGB0   (- 2147483647 - 1) /* INT_MIN */
+#  define FP_ILOGBNAN 2147483647 /* INT_MAX */
+# elif defined __sun
+  /* Solaris 9: match what ilogb() does */
+#  define FP_ILOGB0   (- 2147483647) /* - INT_MAX */
+#  define FP_ILOGBNAN 2147483647 /* INT_MAX */
+# else
+  /* Gnulib defined values.  */
+#  define FP_ILOGB0   (- 2147483647) /* - INT_MAX */
+#  define FP_ILOGBNAN (- 2147483647 - 1) /* INT_MIN */
+# endif
+#endif
+
+
 #if @GNULIB_ACOSF@
 # if !@HAVE_ACOSF@
 #  undef acosf
@@ -1064,6 +1087,67 @@ _GL_WARN_ON_USE (hypotl, "hypotl is unportable - "
 #endif
 
 
+#if @GNULIB_ILOGBF@
+# if @REPLACE_ILOGBF@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef ilogbf
+#   define ilogbf rpl_ilogbf
+#  endif
+_GL_FUNCDECL_RPL (ilogbf, int, (float x));
+_GL_CXXALIAS_RPL (ilogbf, int, (float x));
+# else
+#  if !@HAVE_ILOGBF@
+_GL_FUNCDECL_SYS (ilogbf, int, (float x));
+#  endif
+_GL_CXXALIAS_SYS (ilogbf, int, (float x));
+# endif
+_GL_CXXALIASWARN (ilogbf);
+#elif defined GNULIB_POSIXCHECK
+# undef ilogbf
+# if HAVE_RAW_DECL_ILOGBF
+_GL_WARN_ON_USE (ilogbf, "ilogbf is unportable - "
+                 "use gnulib module ilogbf for portability");
+# endif
+#endif
+
+#if @GNULIB_ILOGB@
+# if @REPLACE_ILOGB@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef ilogb
+#   define ilogb rpl_ilogb
+#  endif
+_GL_FUNCDECL_RPL (ilogb, int, (double x));
+_GL_CXXALIAS_RPL (ilogb, int, (double x));
+# else
+#  if !@HAVE_ILOGB@
+_GL_FUNCDECL_SYS (ilogb, int, (double x));
+#  endif
+_GL_CXXALIAS_SYS (ilogb, int, (double x));
+# endif
+_GL_CXXALIASWARN (ilogb);
+#elif defined GNULIB_POSIXCHECK
+# undef ilogb
+# if HAVE_RAW_DECL_ILOGB
+_GL_WARN_ON_USE (ilogb, "ilogb is unportable - "
+                 "use gnulib module ilogb for portability");
+# endif
+#endif
+
+#if @GNULIB_ILOGBL@
+# if !@HAVE_ILOGBL@
+_GL_FUNCDECL_SYS (ilogbl, int, (long double x));
+# endif
+_GL_CXXALIAS_SYS (ilogbl, int, (long double x));
+_GL_CXXALIASWARN (ilogbl);
+#elif defined GNULIB_POSIXCHECK
+# undef ilogbl
+# if HAVE_RAW_DECL_ILOGBL
+_GL_WARN_ON_USE (ilogbl, "ilogbl is unportable - "
+                 "use gnulib module ilogbl for portability");
+# endif
+#endif
+
+
 /* Return x * 2^exp.  */
 #if @GNULIB_LDEXPF@
 # if !@HAVE_LDEXPF@
@@ -1108,19 +1192,6 @@ _GL_WARN_ON_USE (ldexpl, "ldexpl is unportable - "
 #endif
 
 
-#if @GNULIB_LOGB@
-# if !@HAVE_DECL_LOGB@
-_GL_EXTERN_C double logb (double x);
-# endif
-#elif defined GNULIB_POSIXCHECK
-# undef logb
-# if HAVE_RAW_DECL_LOGB
-_GL_WARN_ON_USE (logb, "logb is unportable - "
-                 "use gnulib module logb for portability");
-# endif
-#endif
-
-
 #if @GNULIB_LOGF@
 # if @REPLACE_LOGF@
 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
@@ -1191,11 +1262,20 @@ _GL_WARN_ON_USE (logl, "logl is unportable - "
 
 
 #if @GNULIB_LOG10F@
-# if !@HAVE_LOG10F@
-#  undef log10f
+# if @REPLACE_LOG10F@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef log10f
+#   define log10f rpl_log10f
+#  endif
+_GL_FUNCDECL_RPL (log10f, float, (float x));
+_GL_CXXALIAS_RPL (log10f, float, (float x));
+# else
+#  if !@HAVE_LOG10F@
+#   undef log10f
 _GL_FUNCDECL_SYS (log10f, float, (float x));
-# endif
+#  endif
 _GL_CXXALIAS_SYS (log10f, float, (float x));
+# endif
 _GL_CXXALIASWARN (log10f);
 #elif defined GNULIB_POSIXCHECK
 # undef log10f
@@ -1205,12 +1285,41 @@ _GL_WARN_ON_USE (log10f, "log10f is unportable - "
 # endif
 #endif
 
+#if @GNULIB_LOG10@
+# if @REPLACE_LOG10@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef log10
+#   define log10 rpl_log10
+#  endif
+_GL_FUNCDECL_RPL (log10, double, (double x));
+_GL_CXXALIAS_RPL (log10, double, (double x));
+# else
+_GL_CXXALIAS_SYS (log10, double, (double x));
+# endif
+_GL_CXXALIASWARN (log10);
+#elif defined GNULIB_POSIXCHECK
+# undef log10
+# if HAVE_RAW_DECL_LOG10
+_GL_WARN_ON_USE (log10, "log10 has portability problems - "
+                 "use gnulib module log10 for portability");
+# endif
+#endif
+
 #if @GNULIB_LOG10L@
-# if !@HAVE_LOG10L@ || !@HAVE_DECL_LOG10L@
-#  undef log10l
+# if @REPLACE_LOG10L@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef log10l
+#   define log10l rpl_log10l
+#  endif
+_GL_FUNCDECL_RPL (log10l, long double, (long double x));
+_GL_CXXALIAS_RPL (log10l, long double, (long double x));
+# else
+#  if !@HAVE_LOG10L@ || !@HAVE_DECL_LOG10L@
+#   undef log10l
 _GL_FUNCDECL_SYS (log10l, long double, (long double x));
-# endif
+#  endif
 _GL_CXXALIAS_SYS (log10l, long double, (long double x));
+# endif
 _GL_CXXALIASWARN (log10l);
 #elif defined GNULIB_POSIXCHECK
 # undef log10l
@@ -1363,6 +1472,76 @@ _GL_WARN_ON_USE (log2l, "log2l is unportable - "
 #endif
 
 
+#if @GNULIB_LOGBF@
+# if @REPLACE_LOGBF@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef logbf
+#   define logbf rpl_logbf
+#  endif
+_GL_FUNCDECL_RPL (logbf, float, (float x));
+_GL_CXXALIAS_RPL (logbf, float, (float x));
+# else
+#  if !@HAVE_LOGBF@
+_GL_FUNCDECL_SYS (logbf, float, (float x));
+#  endif
+_GL_CXXALIAS_SYS (logbf, float, (float x));
+# endif
+_GL_CXXALIASWARN (logbf);
+#elif defined GNULIB_POSIXCHECK
+# undef logbf
+# if HAVE_RAW_DECL_LOGBF
+_GL_WARN_ON_USE (logbf, "logbf is unportable - "
+                 "use gnulib module logbf for portability");
+# endif
+#endif
+
+#if @GNULIB_LOGB@
+# if @REPLACE_LOGB@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef logb
+#   define logb rpl_logb
+#  endif
+_GL_FUNCDECL_RPL (logb, double, (double x));
+_GL_CXXALIAS_RPL (logb, double, (double x));
+# else
+#  if !@HAVE_DECL_LOGB@
+_GL_FUNCDECL_SYS (logb, double, (double x));
+#  endif
+_GL_CXXALIAS_SYS (logb, double, (double x));
+# endif
+_GL_CXXALIASWARN (logb);
+#elif defined GNULIB_POSIXCHECK
+# undef logb
+# if HAVE_RAW_DECL_LOGB
+_GL_WARN_ON_USE (logb, "logb is unportable - "
+                 "use gnulib module logb for portability");
+# endif
+#endif
+
+#if @GNULIB_LOGBL@
+# if @REPLACE_LOGBL@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef logbl
+#   define logbl rpl_logbl
+#  endif
+_GL_FUNCDECL_RPL (logbl, long double, (long double x));
+_GL_CXXALIAS_RPL (logbl, long double, (long double x));
+# else
+#  if !@HAVE_LOGBL@
+_GL_FUNCDECL_SYS (logbl, long double, (long double x));
+#  endif
+_GL_CXXALIAS_SYS (logbl, long double, (long double x));
+# endif
+_GL_CXXALIASWARN (logbl);
+#elif defined GNULIB_POSIXCHECK
+# undef logbl
+# if HAVE_RAW_DECL_LOGBL
+_GL_WARN_ON_USE (logbl, "logbl is unportable - "
+                 "use gnulib module logbl for portability");
+# endif
+#endif
+
+
 #if @GNULIB_MODFF@
 # if @REPLACE_MODFF@
 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
diff --git a/gl/stdio.in.h b/gl/stdio.in.h
index 9dc7c4a646..4d3f0bb7b5 100644
--- a/gl/stdio.in.h
+++ b/gl/stdio.in.h
@@ -698,22 +698,11 @@ _GL_WARN_ON_USE (getline, "getline is unportable - "
 # endif
 #endif
 
-#if @GNULIB_GETS@
-# if @REPLACE_STDIO_READ_FUNCS@ && @GNULIB_STDIO_H_NONBLOCKING@
-#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
-#   undef gets
-#   define gets rpl_gets
-#  endif
-_GL_FUNCDECL_RPL (gets, char *, (char *s) _GL_ARG_NONNULL ((1)));
-_GL_CXXALIAS_RPL (gets, char *, (char *s));
-# else
-_GL_CXXALIAS_SYS (gets, char *, (char *s));
-#  undef gets
-# endif
-_GL_CXXALIASWARN (gets);
 /* It is very rare that the developer ever has full control of stdin,
-   so any use of gets warrants an unconditional warning.  Assume it is
-   always declared, since it is required by C89.  */
+   so any use of gets warrants an unconditional warning; besides, C11
+   removed it.  */
+#undef gets
+#if HAVE_RAW_DECL_GETS
 _GL_WARN_ON_USE (gets, "gets is a security hole - use fgets instead");
 #endif
 
@@ -1053,9 +1042,9 @@ _GL_WARN_ON_USE (snprintf, "snprintf is unportable - "
 # endif
 #endif
 
-/* Some people would argue that sprintf should be handled like gets
-   (for example, OpenBSD issues a link warning for both functions),
-   since both can cause security holes due to buffer overruns.
+/* Some people would argue that all sprintf uses should be warned about
+   (for example, OpenBSD issues a link warning for it),
+   since it can cause security holes due to buffer overruns.
    However, we believe that sprintf can be used safely, and is more
    efficient than snprintf in those safe cases; and as proof of our
    belief, we use sprintf in several gnulib modules.  So this header
diff --git a/gl/stdlib.in.h b/gl/stdlib.in.h
index e92a614cc2..b546133c3a 100644
--- a/gl/stdlib.in.h
+++ b/gl/stdlib.in.h
@@ -94,6 +94,14 @@ struct random_data
 # include <unistd.h>
 #endif
 
+/* The __attribute__ feature is available in gcc versions 2.5 and later.
+   The attribute __pure__ was added in gcc 2.96.  */
+#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
+# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
+#else
+# define _GL_ATTRIBUTE_PURE /* empty */
+#endif
+
 /* The definition of _Noreturn is copied here.  */
 
 /* The definitions of _GL_FUNCDECL_RPL etc. are copied here.  */
@@ -138,7 +146,9 @@ _GL_WARN_ON_USE (_Exit, "_Exit is unportable - "
 /* Parse a signed decimal integer.
    Returns the value of the integer.  Errors are not detected.  */
 # if !@HAVE_ATOLL@
-_GL_FUNCDECL_SYS (atoll, long long, (const char *string) _GL_ARG_NONNULL ((1)));
+_GL_FUNCDECL_SYS (atoll, long long, (const char *string)
+                                    _GL_ATTRIBUTE_PURE
+                                    _GL_ARG_NONNULL ((1)));
 # endif
 _GL_CXXALIAS_SYS (atoll, long long, (const char *string));
 _GL_CXXALIASWARN (atoll);
diff --git a/gl/string.in.h b/gl/string.in.h
index cad18dbec4..f8d7520eaa 100644
--- a/gl/string.in.h
+++ b/gl/string.in.h
@@ -724,10 +724,14 @@ _GL_WARN_ON_USE (strtok_r, "strtok_r is unportable - "
 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
 #   define mbslen rpl_mbslen
 #  endif
-_GL_FUNCDECL_RPL (mbslen, size_t, (const char *string) _GL_ARG_NONNULL ((1)));
+_GL_FUNCDECL_RPL (mbslen, size_t, (const char *string)
+                                  _GL_ATTRIBUTE_PURE
+                                  _GL_ARG_NONNULL ((1)));
 _GL_CXXALIAS_RPL (mbslen, size_t, (const char *string));
 # else
-_GL_FUNCDECL_SYS (mbslen, size_t, (const char *string) _GL_ARG_NONNULL ((1)));
+_GL_FUNCDECL_SYS (mbslen, size_t, (const char *string)
+                                  _GL_ATTRIBUTE_PURE
+                                  _GL_ARG_NONNULL ((1)));
 _GL_CXXALIAS_SYS (mbslen, size_t, (const char *string));
 # endif
 _GL_CXXALIASWARN (mbslen);
@@ -737,6 +741,7 @@ _GL_CXXALIASWARN (mbslen);
 /* Return the number of multibyte characters in the character string starting
    at STRING and ending at STRING + LEN.  */
 _GL_EXTERN_C size_t mbsnlen (const char *string, size_t len)
+     _GL_ATTRIBUTE_PURE
      _GL_ARG_NONNULL ((1));
 #endif
 
@@ -750,10 +755,12 @@ _GL_EXTERN_C size_t mbsnlen (const char *string, size_t len)
 #   define mbschr rpl_mbschr /* avoid collision with HP-UX function */
 #  endif
 _GL_FUNCDECL_RPL (mbschr, char *, (const char *string, int c)
+                                  _GL_ATTRIBUTE_PURE
                                   _GL_ARG_NONNULL ((1)));
 _GL_CXXALIAS_RPL (mbschr, char *, (const char *string, int c));
 # else
 _GL_FUNCDECL_SYS (mbschr, char *, (const char *string, int c)
+                                  _GL_ATTRIBUTE_PURE
                                   _GL_ARG_NONNULL ((1)));
 _GL_CXXALIAS_SYS (mbschr, char *, (const char *string, int c));
 # endif
@@ -770,10 +777,12 @@ _GL_CXXALIASWARN (mbschr);
 #   define mbsrchr rpl_mbsrchr /* avoid collision with system function */
 #  endif
 _GL_FUNCDECL_RPL (mbsrchr, char *, (const char *string, int c)
+                                   _GL_ATTRIBUTE_PURE
                                    _GL_ARG_NONNULL ((1)));
 _GL_CXXALIAS_RPL (mbsrchr, char *, (const char *string, int c));
 # else
 _GL_FUNCDECL_SYS (mbsrchr, char *, (const char *string, int c)
+                                   _GL_ATTRIBUTE_PURE
                                    _GL_ARG_NONNULL ((1)));
 _GL_CXXALIAS_SYS (mbsrchr, char *, (const char *string, int c));
 # endif
@@ -786,6 +795,7 @@ _GL_CXXALIASWARN (mbsrchr);
    Unlike strstr(), this function works correctly in multibyte locales with
    encodings different from UTF-8.  */
 _GL_EXTERN_C char * mbsstr (const char *haystack, const char *needle)
+     _GL_ATTRIBUTE_PURE
      _GL_ARG_NONNULL ((1, 2));
 #endif
 
@@ -797,6 +807,7 @@ _GL_EXTERN_C char * mbsstr (const char *haystack, const char *needle)
    different lengths!
    Unlike strcasecmp(), this function works correctly in multibyte locales.  */
 _GL_EXTERN_C int mbscasecmp (const char *s1, const char *s2)
+     _GL_ATTRIBUTE_PURE
      _GL_ARG_NONNULL ((1, 2));
 #endif
 
@@ -811,6 +822,7 @@ _GL_EXTERN_C int mbscasecmp (const char *s1, const char *s2)
    Unlike strncasecmp(), this function works correctly in multibyte locales.
    But beware that N is not a byte count but a character count!  */
 _GL_EXTERN_C int mbsncasecmp (const char *s1, const char *s2, size_t n)
+     _GL_ATTRIBUTE_PURE
      _GL_ARG_NONNULL ((1, 2));
 #endif
 
@@ -824,6 +836,7 @@ _GL_EXTERN_C int mbsncasecmp (const char *s1, const char *s2, size_t n)
    Unlike strncasecmp(), this function works correctly in multibyte
    locales.  */
 _GL_EXTERN_C char * mbspcasecmp (const char *string, const char *prefix)
+     _GL_ATTRIBUTE_PURE
      _GL_ARG_NONNULL ((1, 2));
 #endif
 
@@ -834,6 +847,7 @@ _GL_EXTERN_C char * mbspcasecmp (const char *string, const char *prefix)
    strlen (haystack) < strlen (needle) !
    Unlike strcasestr(), this function works correctly in multibyte locales.  */
 _GL_EXTERN_C char * mbscasestr (const char *haystack, const char *needle)
+     _GL_ATTRIBUTE_PURE
      _GL_ARG_NONNULL ((1, 2));
 #endif
 
@@ -844,6 +858,7 @@ _GL_EXTERN_C char * mbscasestr (const char *haystack, const char *needle)
    if none exists.
    Unlike strcspn(), this function works correctly in multibyte locales.  */
 _GL_EXTERN_C size_t mbscspn (const char *string, const char *accept)
+     _GL_ATTRIBUTE_PURE
      _GL_ARG_NONNULL ((1, 2));
 #endif
 
@@ -857,10 +872,12 @@ _GL_EXTERN_C size_t mbscspn (const char *string, const char *accept)
 #   define mbspbrk rpl_mbspbrk /* avoid collision with HP-UX function */
 #  endif
 _GL_FUNCDECL_RPL (mbspbrk, char *, (const char *string, const char *accept)
+                                   _GL_ATTRIBUTE_PURE
                                    _GL_ARG_NONNULL ((1, 2)));
 _GL_CXXALIAS_RPL (mbspbrk, char *, (const char *string, const char *accept));
 # else
 _GL_FUNCDECL_SYS (mbspbrk, char *, (const char *string, const char *accept)
+                                   _GL_ATTRIBUTE_PURE
                                    _GL_ARG_NONNULL ((1, 2)));
 _GL_CXXALIAS_SYS (mbspbrk, char *, (const char *string, const char *accept));
 # endif
@@ -874,6 +891,7 @@ _GL_CXXALIASWARN (mbspbrk);
    if none exists.
    Unlike strspn(), this function works correctly in multibyte locales.  */
 _GL_EXTERN_C size_t mbsspn (const char *string, const char *reject)
+     _GL_ATTRIBUTE_PURE
      _GL_ARG_NONNULL ((1, 2));
 #endif
 
@@ -993,6 +1011,7 @@ _GL_WARN_ON_USE (strsignal, "strsignal is unportable - "
 #if @GNULIB_STRVERSCMP@
 # if !@HAVE_STRVERSCMP@
 _GL_FUNCDECL_SYS (strverscmp, int, (const char *, const char *)
+                                   _GL_ATTRIBUTE_PURE
                                    _GL_ARG_NONNULL ((1, 2)));
 # endif
 _GL_CXXALIAS_SYS (strverscmp, int, (const char *, const char *));
diff --git a/gl/tests/strerror_r.c b/gl/tests/strerror_r.c
index be76b0d37a..76f6fc64d2 100644
--- a/gl/tests/strerror_r.c
+++ b/gl/tests/strerror_r.c
@@ -34,6 +34,7 @@
 #if (__GLIBC__ >= 2 || defined __UCLIBC__ || defined __CYGWIN__) && HAVE___XPG_STRERROR_R /* glibc >= 2.3.4, cygwin >= 1.7.9 */
 
 # define USE_XPG_STRERROR_R 1
+extern int __xpg_strerror_r (int errnum, char *buf, size_t buflen);
 
 #elif HAVE_DECL_STRERROR_R && !(__GLIBC__ >= 2 || defined __UCLIBC__ || defined __CYGWIN__)
 
@@ -161,8 +162,6 @@ strerror_r (int errnum, char *buf, size_t buflen)
 #if USE_XPG_STRERROR_R
 
     {
-      extern int __xpg_strerror_r (int errnum, char *buf, size_t buflen);
-
       ret = __xpg_strerror_r (errnum, buf, buflen);
       if (ret < 0)
         ret = errno;
diff --git a/gl/tests/test-float.c b/gl/tests/test-float.c
index f3691be5e1..18da40b5e9 100644
--- a/gl/tests/test-float.c
+++ b/gl/tests/test-float.c
@@ -23,11 +23,11 @@
 #include "fpucw.h"
 #include "macros.h"
 
+#if 0
+
 /* Check that FLT_RADIX is a constant expression.  */
 int a[] = { FLT_RADIX };
 
-#if FLT_RADIX == 2
-
 /* Return 2^n.  */
 static float
 pow2f (int n)
@@ -377,7 +377,6 @@ main ()
 int
 main ()
 {
-  fprintf (stderr, "Skipping test: FLT_RADIX is not 2.\n");
   return 77;
 }
 
diff --git a/gl/tests/test-math.c b/gl/tests/test-math.c
index 25be63a54d..1375e76ad4 100644
--- a/gl/tests/test-math.c
+++ b/gl/tests/test-math.c
@@ -40,6 +40,18 @@ choke me
 choke me
 #endif
 
+#ifndef FP_ILOGB0
+# error FP_ILOGB0 should be defined
+choke me
+#endif
+
+#ifndef FP_ILOGBNAN
+# error FP_ILOGBNAN should be defined
+choke me
+#endif
+
+#include <limits.h>
+
 #include "macros.h"
 
 #if 0
@@ -82,5 +94,11 @@ main (void)
 
   ASSERT (numeric_equall (HUGE_VALL, HUGE_VALL + HUGE_VALL));
 
+  /* Check the value of FP_ILOGB0.  */
+  ASSERT (FP_ILOGB0 == INT_MIN || FP_ILOGB0 == - INT_MAX);
+
+  /* Check the value of FP_ILOGBNAN.  */
+  ASSERT (FP_ILOGBNAN == INT_MIN || FP_ILOGBNAN == INT_MAX);
+
   return 0;
 }
diff --git a/gl/wchar.in.h b/gl/wchar.in.h
index 4e92a77802..f9bc30c030 100644
--- a/gl/wchar.in.h
+++ b/gl/wchar.in.h
@@ -83,6 +83,14 @@
 #ifndef _@GUARD_PREFIX@_WCHAR_H
 #define _@GUARD_PREFIX@_WCHAR_H
 
+/* The __attribute__ feature is available in gcc versions 2.5 and later.
+   The attribute __pure__ was added in gcc 2.96.  */
+#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
+# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
+#else
+# define _GL_ATTRIBUTE_PURE /* empty */
+#endif
+
 /* The definitions of _GL_FUNCDECL_RPL etc. are copied here.  */
 
 /* The definition of _GL_ARG_NONNULL is copied here.  */
@@ -135,11 +143,11 @@ typedef int rpl_mbstate_t;
 #   undef btowc
 #   define btowc rpl_btowc
 #  endif
-_GL_FUNCDECL_RPL (btowc, wint_t, (int c));
+_GL_FUNCDECL_RPL (btowc, wint_t, (int c) _GL_ATTRIBUTE_PURE);
 _GL_CXXALIAS_RPL (btowc, wint_t, (int c));
 # else
 #  if !@HAVE_BTOWC@
-_GL_FUNCDECL_SYS (btowc, wint_t, (int c));
+_GL_FUNCDECL_SYS (btowc, wint_t, (int c) _GL_ATTRIBUTE_PURE);
 #  endif
 _GL_CXXALIAS_SYS (btowc, wint_t, (int c));
 # endif
@@ -160,12 +168,12 @@ _GL_WARN_ON_USE (btowc, "btowc is unportable - "
 #   undef wctob
 #   define wctob rpl_wctob
 #  endif
-_GL_FUNCDECL_RPL (wctob, int, (wint_t wc));
+_GL_FUNCDECL_RPL (wctob, int, (wint_t wc) _GL_ATTRIBUTE_PURE);
 _GL_CXXALIAS_RPL (wctob, int, (wint_t wc));
 # else
 #  if !defined wctob && !@HAVE_DECL_WCTOB@
 /* wctob is provided by gnulib, or wctob exists but is not declared.  */
-_GL_FUNCDECL_SYS (wctob, int, (wint_t wc));
+_GL_FUNCDECL_SYS (wctob, int, (wint_t wc) _GL_ATTRIBUTE_PURE);
 #  endif
 _GL_CXXALIAS_SYS (wctob, int, (wint_t wc));
 # endif
@@ -426,12 +434,12 @@ _GL_WARN_ON_USE (wcsnrtombs, "wcsnrtombs is unportable - "
 #   undef wcwidth
 #   define wcwidth rpl_wcwidth
 #  endif
-_GL_FUNCDECL_RPL (wcwidth, int, (wchar_t));
+_GL_FUNCDECL_RPL (wcwidth, int, (wchar_t) _GL_ATTRIBUTE_PURE);
 _GL_CXXALIAS_RPL (wcwidth, int, (wchar_t));
 # else
 #  if !@HAVE_DECL_WCWIDTH@
 /* wcwidth exists but is not declared.  */
-_GL_FUNCDECL_SYS (wcwidth, int, (wchar_t));
+_GL_FUNCDECL_SYS (wcwidth, int, (wchar_t) _GL_ATTRIBUTE_PURE);
 #  endif
 _GL_CXXALIAS_SYS (wcwidth, int, (wchar_t));
 # endif
@@ -448,7 +456,8 @@ _GL_WARN_ON_USE (wcwidth, "wcwidth is unportable - "
 /* Search N wide characters of S for C.  */
 #if @GNULIB_WMEMCHR@
 # if !@HAVE_WMEMCHR@
-_GL_FUNCDECL_SYS (wmemchr, wchar_t *, (const wchar_t *s, wchar_t c, size_t n));
+_GL_FUNCDECL_SYS (wmemchr, wchar_t *, (const wchar_t *s, wchar_t c, size_t n)
+                                      _GL_ATTRIBUTE_PURE);
 # endif
   /* On some systems, this function is defined as an overloaded function:
        extern "C++" {
@@ -479,7 +488,8 @@ _GL_WARN_ON_USE (wmemchr, "wmemchr is unportable - "
 #if @GNULIB_WMEMCMP@
 # if !@HAVE_WMEMCMP@
 _GL_FUNCDECL_SYS (wmemcmp, int,
-                  (const wchar_t *s1, const wchar_t *s2, size_t n));
+                  (const wchar_t *s1, const wchar_t *s2, size_t n)
+                  _GL_ATTRIBUTE_PURE);
 # endif
 _GL_CXXALIAS_SYS (wmemcmp, int,
                   (const wchar_t *s1, const wchar_t *s2, size_t n));
@@ -549,7 +559,7 @@ _GL_WARN_ON_USE (wmemset, "wmemset is unportable - "
 /* Return the number of wide characters in S.  */
 #if @GNULIB_WCSLEN@
 # if !@HAVE_WCSLEN@
-_GL_FUNCDECL_SYS (wcslen, size_t, (const wchar_t *s));
+_GL_FUNCDECL_SYS (wcslen, size_t, (const wchar_t *s) _GL_ATTRIBUTE_PURE);
 # endif
 _GL_CXXALIAS_SYS (wcslen, size_t, (const wchar_t *s));
 _GL_CXXALIASWARN (wcslen);
@@ -565,7 +575,8 @@ _GL_WARN_ON_USE (wcslen, "wcslen is unportable - "
 /* Return the number of wide characters in S, but at most MAXLEN.  */
 #if @GNULIB_WCSNLEN@
 # if !@HAVE_WCSNLEN@
-_GL_FUNCDECL_SYS (wcsnlen, size_t, (const wchar_t *s, size_t maxlen));
+_GL_FUNCDECL_SYS (wcsnlen, size_t, (const wchar_t *s, size_t maxlen)
+                                   _GL_ATTRIBUTE_PURE);
 # endif
 _GL_CXXALIAS_SYS (wcsnlen, size_t, (const wchar_t *s, size_t maxlen));
 _GL_CXXALIASWARN (wcsnlen);
@@ -684,7 +695,8 @@ _GL_WARN_ON_USE (wcsncat, "wcsncat is unportable - "
 /* Compare S1 and S2.  */
 #if @GNULIB_WCSCMP@
 # if !@HAVE_WCSCMP@
-_GL_FUNCDECL_SYS (wcscmp, int, (const wchar_t *s1, const wchar_t *s2));
+_GL_FUNCDECL_SYS (wcscmp, int, (const wchar_t *s1, const wchar_t *s2)
+                               _GL_ATTRIBUTE_PURE);
 # endif
 _GL_CXXALIAS_SYS (wcscmp, int, (const wchar_t *s1, const wchar_t *s2));
 _GL_CXXALIASWARN (wcscmp);
@@ -701,7 +713,8 @@ _GL_WARN_ON_USE (wcscmp, "wcscmp is unportable - "
 #if @GNULIB_WCSNCMP@
 # if !@HAVE_WCSNCMP@
 _GL_FUNCDECL_SYS (wcsncmp, int,
-                  (const wchar_t *s1, const wchar_t *s2, size_t n));
+                  (const wchar_t *s1, const wchar_t *s2, size_t n)
+                  _GL_ATTRIBUTE_PURE);
 # endif
 _GL_CXXALIAS_SYS (wcsncmp, int,
                   (const wchar_t *s1, const wchar_t *s2, size_t n));
@@ -718,7 +731,8 @@ _GL_WARN_ON_USE (wcsncmp, "wcsncmp is unportable - "
 /* Compare S1 and S2, ignoring case.  */
 #if @GNULIB_WCSCASECMP@
 # if !@HAVE_WCSCASECMP@
-_GL_FUNCDECL_SYS (wcscasecmp, int, (const wchar_t *s1, const wchar_t *s2));
+_GL_FUNCDECL_SYS (wcscasecmp, int, (const wchar_t *s1, const wchar_t *s2)
+                                   _GL_ATTRIBUTE_PURE);
 # endif
 _GL_CXXALIAS_SYS (wcscasecmp, int, (const wchar_t *s1, const wchar_t *s2));
 _GL_CXXALIASWARN (wcscasecmp);
@@ -735,7 +749,8 @@ _GL_WARN_ON_USE (wcscasecmp, "wcscasecmp is unportable - "
 #if @GNULIB_WCSNCASECMP@
 # if !@HAVE_WCSNCASECMP@
 _GL_FUNCDECL_SYS (wcsncasecmp, int,
-                  (const wchar_t *s1, const wchar_t *s2, size_t n));
+                  (const wchar_t *s1, const wchar_t *s2, size_t n)
+                  _GL_ATTRIBUTE_PURE);
 # endif
 _GL_CXXALIAS_SYS (wcsncasecmp, int,
                   (const wchar_t *s1, const wchar_t *s2, size_t n));
@@ -803,7 +818,8 @@ _GL_WARN_ON_USE (wcsdup, "wcsdup is unportable - "
 /* Find the first occurrence of WC in WCS.  */
 #if @GNULIB_WCSCHR@
 # if !@HAVE_WCSCHR@
-_GL_FUNCDECL_SYS (wcschr, wchar_t *, (const wchar_t *wcs, wchar_t wc));
+_GL_FUNCDECL_SYS (wcschr, wchar_t *, (const wchar_t *wcs, wchar_t wc)
+                                     _GL_ATTRIBUTE_PURE);
 # endif
   /* On some systems, this function is defined as an overloaded function:
        extern "C++" {
@@ -832,7 +848,8 @@ _GL_WARN_ON_USE (wcschr, "wcschr is unportable - "
 /* Find the last occurrence of WC in WCS.  */
 #if @GNULIB_WCSRCHR@
 # if !@HAVE_WCSRCHR@
-_GL_FUNCDECL_SYS (wcsrchr, wchar_t *, (const wchar_t *wcs, wchar_t wc));
+_GL_FUNCDECL_SYS (wcsrchr, wchar_t *, (const wchar_t *wcs, wchar_t wc)
+                                      _GL_ATTRIBUTE_PURE);
 # endif
   /* On some systems, this function is defined as an overloaded function:
        extern "C++" {
@@ -862,7 +879,8 @@ _GL_WARN_ON_USE (wcsrchr, "wcsrchr is unportable - "
    of wide characters not in REJECT.  */
 #if @GNULIB_WCSCSPN@
 # if !@HAVE_WCSCSPN@
-_GL_FUNCDECL_SYS (wcscspn, size_t, (const wchar_t *wcs, const wchar_t *reject));
+_GL_FUNCDECL_SYS (wcscspn, size_t, (const wchar_t *wcs, const wchar_t *reject)
+                                   _GL_ATTRIBUTE_PURE);
 # endif
 _GL_CXXALIAS_SYS (wcscspn, size_t, (const wchar_t *wcs, const wchar_t *reject));
 _GL_CXXALIASWARN (wcscspn);
@@ -879,7 +897,8 @@ _GL_WARN_ON_USE (wcscspn, "wcscspn is unportable - "
    of wide characters in ACCEPT.  */
 #if @GNULIB_WCSSPN@
 # if !@HAVE_WCSSPN@
-_GL_FUNCDECL_SYS (wcsspn, size_t, (const wchar_t *wcs, const wchar_t *accept));
+_GL_FUNCDECL_SYS (wcsspn, size_t, (const wchar_t *wcs, const wchar_t *accept)
+                                  _GL_ATTRIBUTE_PURE);
 # endif
 _GL_CXXALIAS_SYS (wcsspn, size_t, (const wchar_t *wcs, const wchar_t *accept));
 _GL_CXXALIASWARN (wcsspn);
@@ -896,7 +915,8 @@ _GL_WARN_ON_USE (wcsspn, "wcsspn is unportable - "
 #if @GNULIB_WCSPBRK@
 # if !@HAVE_WCSPBRK@
 _GL_FUNCDECL_SYS (wcspbrk, wchar_t *,
-                  (const wchar_t *wcs, const wchar_t *accept));
+                  (const wchar_t *wcs, const wchar_t *accept)
+                  _GL_ATTRIBUTE_PURE);
 # endif
   /* On some systems, this function is defined as an overloaded function:
        extern "C++" {
@@ -928,7 +948,8 @@ _GL_WARN_ON_USE (wcspbrk, "wcspbrk is unportable - "
 #if @GNULIB_WCSSTR@
 # if !@HAVE_WCSSTR@
 _GL_FUNCDECL_SYS (wcsstr, wchar_t *,
-                  (const wchar_t *haystack, const wchar_t *needle));
+                  (const wchar_t *haystack, const wchar_t *needle)
+                  _GL_ATTRIBUTE_PURE);
 # endif
   /* On some systems, this function is defined as an overloaded function:
        extern "C++" {
@@ -982,11 +1003,13 @@ _GL_WARN_ON_USE (wcstok, "wcstok is unportable - "
 #   undef wcswidth
 #   define wcswidth rpl_wcswidth
 #  endif
-_GL_FUNCDECL_RPL (wcswidth, int, (const wchar_t *s, size_t n));
+_GL_FUNCDECL_RPL (wcswidth, int, (const wchar_t *s, size_t n)
+                                 _GL_ATTRIBUTE_PURE);
 _GL_CXXALIAS_RPL (wcswidth, int, (const wchar_t *s, size_t n));
 # else
 #  if !@HAVE_WCSWIDTH@
-_GL_FUNCDECL_SYS (wcswidth, int, (const wchar_t *s, size_t n));
+_GL_FUNCDECL_SYS (wcswidth, int, (const wchar_t *s, size_t n)
+                                 _GL_ATTRIBUTE_PURE);
 #  endif
 _GL_CXXALIAS_SYS (wcswidth, int, (const wchar_t *s, size_t n));
 # endif