printf, isinf, etc.: noncanonical != NaN

Do not require that isinf, printf, etc. treat noncanonical
values as NaNs.  Instead, require only that they do not crash.
Problem reported by Joseph Myers in:
https://sourceware.org/ml/libc-alpha/2015-02/msg00244.html
* doc/posix-functions/dprintf.texi (dprintf):
* doc/posix-functions/fprintf.texi (fprintf):
* doc/posix-functions/isfinite.texi (isfinite):
* doc/posix-functions/isinf.texi (isinf):
* doc/posix-functions/isnan.texi (isnan):
* doc/posix-functions/printf.texi (printf):
* doc/posix-functions/snprintf.texi (snprintf):
* doc/posix-functions/sprintf.texi (sprintf):
* doc/posix-functions/vdprintf.texi (vdprintf):
* doc/posix-functions/vfprintf.texi (vfprintf):
* doc/posix-functions/vprintf.texi (vprintf):
* doc/posix-functions/vsnprintf.texi (vsnprintf):
* doc/posix-functions/vsprintf.texi (vsprintf):
Document this.
* m4/isfinite.m4 (gl_ISFINITEL_WORKS):
* m4/isinf.m4 (gl_ISINFL_WORKS):
* m4/isnanl.m4 (gl_FUNC_ISNANL_WORKS):
* m4/printf.m4 (gl_PRINTF_INFINITE_LONG_DOUBLE):
* tests/test-isfinite.c (test_isfinitel):
* tests/test-isinf.c (test_isinfl):
* tests/test-isnan.c (test_long_double):
* tests/test-isnanl.h (main):
* tests/test-snprintf-posix.h (test_function):
* tests/test-sprintf-posix.h (test_function):
* tests/test-vasnprintf-posix.c (test_function):
* tests/test-vasprintf-posix.c (test_function):
o	Test only that noncanonical values do not cause crashes, not that
they are treated as NaNs.  In some cases this means a larger
output buffer is needed.

13 files changed, 52 insertions, 59 deletions

diff --git a/doc/posix-functions/dprintf.texi b/doc/posix-functions/dprintf.texi
index 41b8e4424e..acc752cc00 100644
--- a/doc/posix-functions/dprintf.texi
+++ b/doc/posix-functions/dprintf.texi
@@ -17,10 +17,6 @@ IRIX 6.5, OSF/1 5.1, Solaris 11 2011-11, Cygwin 1.5.x, mingw, MSVC 9, Interix 3.
 Portability problems fixed by Gnulib module @code{dprintf-posix}:
 @itemize
 @item
-printf of @samp{long double} numbers outside the IEEE 754 range produces
-no meaningful results on some platforms:
-glibc and others, on x86, x86_64, IA-64 CPUs.
-@item
 This function does not support the @samp{a} and @samp{A} directives on some
 platforms:
 glibc-2.3.6.
@@ -33,6 +29,10 @@ AIX 7.1.
 Portability problems not fixed by Gnulib:
 @itemize
 @item
+Formatting noncanonical @samp{long double} numbers produces
+nonmeaningful results on some platforms:
+glibc and others, on x86, x86_64, IA-64 CPUs.
+@item
 When formatting an integer with grouping flag, this function inserts thousands
 separators even in the "C" locale on some platforms:
 NetBSD 5.1.
diff --git a/doc/posix-functions/fprintf.texi b/doc/posix-functions/fprintf.texi
index 3916b3123f..f4a6d5e75d 100644
--- a/doc/posix-functions/fprintf.texi
+++ b/doc/posix-functions/fprintf.texi
@@ -20,10 +20,6 @@ printf @code{"%f"}, @code{"%e"}, @code{"%g"} of Infinity and NaN yields an
 incorrect result on some platforms:
 AIX 5.2, OSF/1 5.1, Solaris 11 2011-11, mingw, MSVC 9.
 @item
-printf of @samp{long double} numbers outside the IEEE 754 range produces
-no meaningful results on some platforms:
-glibc and others, on x86, x86_64, IA-64 CPUs.
-@item
 This function does not support the @samp{a} and @samp{A} directives on some
 platforms:
 glibc-2.3.6, Mac OS X 10.5, NetBSD 5.0, OpenBSD 4.0, AIX 5.2, HP-UX 11,
@@ -91,6 +87,10 @@ mingw, MSVC 9.
 Portability problems not fixed by Gnulib:
 @itemize
 @item
+Formatting noncanonical @samp{long double} numbers produces
+nonmeaningful results on some platforms:
+glibc and others, on x86, x86_64, IA-64 CPUs.
+@item
 When formatting an integer with grouping flag, this function inserts thousands
 separators even in the "C" locale on some platforms:
 NetBSD 5.1.
diff --git a/doc/posix-functions/isfinite.texi b/doc/posix-functions/isfinite.texi
index 3e6f3d8ee0..32fe0b86b5 100644
--- a/doc/posix-functions/isfinite.texi
+++ b/doc/posix-functions/isfinite.texi
@@ -15,12 +15,6 @@ Mac OS X 10.5, OpenBSD 3.8, AIX 5.1, IRIX 6.5, OSF/1 5.1, Solaris 11 2011-11, In
 This macro incorrectly yields true for some @samp{double} arguments, on some
 platforms:
 Linux/ia64 (signalling NaNs).
-@item
-This macro incorrectly yields true for some @samp{long double} arguments, on
-some platforms:
-x86 (pseudo-zeroes, unnormalized numbers, pseudo-denormals),
-x86_64 (pseudo-denormals),
-ia64 (pseudo-NaN, pseudo-Infinity, pseudo-zeroes, unnormalized numbers, pseudo-denormals).
 @end itemize
 
 Portability problems not fixed by Gnulib:
@@ -28,4 +22,8 @@ Portability problems not fixed by Gnulib:
 @item
 It is implementation-dependent whether @code{isfinite} raises an
 exception given a signaling NaN operand.
+@item
+This macro returns an unspecified result when given noncanonical values
+such as unnormalized numbers, pseudo-denormals, pseudo-NaNs,
+pseudo-Infinities, and pseudo-zeroes.
 @end itemize
diff --git a/doc/posix-functions/isinf.texi b/doc/posix-functions/isinf.texi
index 2448d75706..848d1e6cc4 100644
--- a/doc/posix-functions/isinf.texi
+++ b/doc/posix-functions/isinf.texi
@@ -11,12 +11,12 @@ Portability problems fixed by Gnulib:
 @item
 This macro is missing on some platforms:
 AIX 5.1, IRIX 6.5, OSF/1 5.1, Solaris 11 2011-11.
-@item
-This macro incorrectly yields true for some @samp{long double} arguments, on
-some platforms:
-OpenBSD 4.9/x86 (pseudo-Infinity).
 @end itemize
 
 Portability problems not fixed by Gnulib:
 @itemize
+@item
+This macro returns an unspecified result when given noncanonical values
+such as unnormalized numbers, pseudo-denormals, pseudo-NaNs,
+pseudo-Infinities, and pseudo-zeroes.
 @end itemize
diff --git a/doc/posix-functions/isnan.texi b/doc/posix-functions/isnan.texi
index 160b7a4627..f9ed11a6b5 100644
--- a/doc/posix-functions/isnan.texi
+++ b/doc/posix-functions/isnan.texi
@@ -19,17 +19,12 @@ on pre-C99 systems.
 IRIX 6.5, OSF/1 5.1 with gcc, Solaris 11 2011-11.
 @item
 On IRIX 6.5 with @code{cc}, @code{isnan} does not recognize some NaNs.
-@item
-On NetBSD/i386 and glibc/ia64, @code{isnan} does not recognize some
-forms of NaNs, such as pseudo-NaNs, pseudo-Infinities, and
-unnormalized numbers.
-@item
-On i686 and @var{x}86-64, @code{__builtin_isnanl} (and thus
-@code{isnan} implementations based on it) in GCC 4.0 and later does
-not recognize pseudo-denormals as NaNs, and similarly for
-pseudo-zeroes, unnormalized numbers, and pseudo-denormals on ia64.
 @end itemize
 
 Portability problems not fixed by Gnulib:
 @itemize
+@item
+This macro returns an unspecified result when given noncanonical values
+such as unnormalized numbers, pseudo-denormals, pseudo-NaNs,
+pseudo-Infinities, and pseudo-zeroes.
 @end itemize
diff --git a/doc/posix-functions/printf.texi b/doc/posix-functions/printf.texi
index b96dd95cd0..79537c973e 100644
--- a/doc/posix-functions/printf.texi
+++ b/doc/posix-functions/printf.texi
@@ -20,10 +20,6 @@ printf @code{"%f"}, @code{"%e"}, @code{"%g"} of Infinity and NaN yields an
 incorrect result on some platforms:
 AIX 5.2, OSF/1 5.1, Solaris 11 2011-11, mingw, MSVC 9.
 @item
-printf of @samp{long double} numbers outside the IEEE 754 range produces
-no meaningful results on some platforms:
-glibc and others, on x86, x86_64, IA-64 CPUs.
-@item
 This function does not support the @samp{a} and @samp{A} directives on some
 platforms:
 glibc-2.3.6, Mac OS X 10.5, NetBSD 5.0, OpenBSD 4.0, AIX 5.2, HP-UX 11,
@@ -91,6 +87,10 @@ mingw, MSVC 9.
 Portability problems not fixed by Gnulib:
 @itemize
 @item
+Formatting noncanonical @samp{long double} numbers produces
+nonmeaningful results on some platforms:
+glibc and others, on x86, x86_64, IA-64 CPUs.
+@item
 When formatting an integer with grouping flag, this function inserts thousands
 separators even in the "C" locale on some platforms:
 NetBSD 5.1.
diff --git a/doc/posix-functions/snprintf.texi b/doc/posix-functions/snprintf.texi
index 3d90c30d83..76c88fa193 100644
--- a/doc/posix-functions/snprintf.texi
+++ b/doc/posix-functions/snprintf.texi
@@ -39,10 +39,6 @@ printf @code{"%f"}, @code{"%e"}, @code{"%g"} of Infinity and NaN yields an
 incorrect result on some platforms:
 AIX 5.2, OSF/1 5.1, Solaris 11 2011-11, mingw, MSVC 9.
 @item
-printf of @samp{long double} numbers outside the IEEE 754 range produces
-no meaningful results on some platforms:
-glibc and others, on x86, x86_64, IA-64 CPUs.
-@item
 This function does not support the @samp{a} and @samp{A} directives on some
 platforms:
 glibc-2.3.6, Mac OS X 10.5, NetBSD 5.0, OpenBSD 4.0, AIX 5.2, HP-UX 11,
@@ -99,6 +95,10 @@ OSF/1 5.1.
 Portability problems not fixed by Gnulib:
 @itemize
 @item
+Formatting noncanonical @samp{long double} numbers produces
+nonmeaningful results on some platforms:
+glibc and others, on x86, x86_64, IA-64 CPUs.
+@item
 When formatting an integer with grouping flag, this function inserts thousands
 separators even in the "C" locale on some platforms:
 NetBSD 5.1.
diff --git a/doc/posix-functions/sprintf.texi b/doc/posix-functions/sprintf.texi
index b4c4549cfa..63b38bf8cb 100644
--- a/doc/posix-functions/sprintf.texi
+++ b/doc/posix-functions/sprintf.texi
@@ -20,10 +20,6 @@ printf @code{"%f"}, @code{"%e"}, @code{"%g"} of Infinity and NaN yields an
 incorrect result on some platforms:
 AIX 5.2, OSF/1 5.1, Solaris 11 2011-11, mingw, MSVC 9.
 @item
-printf of @samp{long double} numbers outside the IEEE 754 range produces
-no meaningful results on some platforms:
-glibc and others, on x86, x86_64, IA-64 CPUs.
-@item
 This function does not support the @samp{a} and @samp{A} directives on some
 platforms:
 glibc-2.3.6, Mac OS X 10.5, NetBSD 5.0, OpenBSD 4.0, AIX 5.2, HP-UX 11,
@@ -74,6 +70,10 @@ Mac OS X 10.3, FreeBSD 6.0, NetBSD 5.0.
 Portability problems not fixed by Gnulib:
 @itemize
 @item
+Formatting noncanonical @samp{long double} numbers produces
+nonmeaningful results on some platforms:
+glibc and others, on x86, x86_64, IA-64 CPUs.
+@item
 When formatting an integer with grouping flag, this function inserts thousands
 separators even in the "C" locale on some platforms:
 NetBSD 5.1.
diff --git a/doc/posix-functions/vdprintf.texi b/doc/posix-functions/vdprintf.texi
index 78e0f00bf6..72f4b9314e 100644
--- a/doc/posix-functions/vdprintf.texi
+++ b/doc/posix-functions/vdprintf.texi
@@ -24,10 +24,6 @@ BeOS.
 printf of @samp{long double} numbers is unsupported on some platforms:
 BeOS.
 @item
-printf of @samp{long double} numbers outside the IEEE 754 range produces
-no meaningful results on some platforms:
-glibc and others, on x86, x86_64, IA-64 CPUs.
-@item
 This function does not support the @samp{a} and @samp{A} directives on some
 platforms:
 glibc-2.3.6, BeOS.
@@ -47,6 +43,10 @@ AIX 7.1, BeOS.
 Portability problems not fixed by Gnulib:
 @itemize
 @item
+Formatting noncanonical @samp{long double} numbers produces
+nonmeaningful results on some platforms:
+glibc and others, on x86, x86_64, IA-64 CPUs.
+@item
 When formatting an integer with grouping flag, this function inserts thousands
 separators even in the "C" locale on some platforms:
 NetBSD 5.1.
diff --git a/doc/posix-functions/vfprintf.texi b/doc/posix-functions/vfprintf.texi
index ea70658073..00f103fea9 100644
--- a/doc/posix-functions/vfprintf.texi
+++ b/doc/posix-functions/vfprintf.texi
@@ -20,10 +20,6 @@ printf @code{"%f"}, @code{"%e"}, @code{"%g"} of Infinity and NaN yields an
 incorrect result on some platforms:
 AIX 5.2, OSF/1 5.1, Solaris 11 2011-11, mingw, MSVC 9.
 @item
-printf of @samp{long double} numbers outside the IEEE 754 range produces
-no meaningful results on some platforms:
-glibc and others, on x86, x86_64, IA-64 CPUs.
-@item
 This function does not support the @samp{a} and @samp{A} directives on some
 platforms:
 glibc-2.3.6, Mac OS X 10.5, NetBSD 5.0, OpenBSD 4.0, AIX 5.2, HP-UX 11,
@@ -91,6 +87,10 @@ mingw, MSVC 9.
 Portability problems not fixed by Gnulib:
 @itemize
 @item
+Formatting noncanonical @samp{long double} numbers produces
+nonmeaningful results on some platforms:
+glibc and others, on x86, x86_64, IA-64 CPUs.
+@item
 When formatting an integer with grouping flag, this function inserts thousands
 separators even in the "C" locale on some platforms:
 NetBSD 5.1.
diff --git a/doc/posix-functions/vprintf.texi b/doc/posix-functions/vprintf.texi
index 72ab1040c5..a7bcf51d89 100644
--- a/doc/posix-functions/vprintf.texi
+++ b/doc/posix-functions/vprintf.texi
@@ -20,10 +20,6 @@ printf @code{"%f"}, @code{"%e"}, @code{"%g"} of Infinity and NaN yields an
 incorrect result on some platforms:
 AIX 5.2, OSF/1 5.1, Solaris 11 2011-11, mingw, MSVC 9.
 @item
-printf of @samp{long double} numbers outside the IEEE 754 range produces
-no meaningful results on some platforms:
-glibc and others, on x86, x86_64, IA-64 CPUs.
-@item
 This function does not support the @samp{a} and @samp{A} directives on some
 platforms:
 glibc-2.3.6, Mac OS X 10.5, NetBSD 5.0, OpenBSD 4.0, AIX 5.2, HP-UX 11,
@@ -91,6 +87,10 @@ mingw, MSVC 9.
 Portability problems not fixed by Gnulib:
 @itemize
 @item
+Formatting noncanonical @samp{long double} numbers produces
+nonmeaningful results on some platforms:
+glibc and others, on x86, x86_64, IA-64 CPUs.
+@item
 When formatting an integer with grouping flag, this function inserts thousands
 separators even in the "C" locale on some platforms:
 NetBSD 5.1.
diff --git a/doc/posix-functions/vsnprintf.texi b/doc/posix-functions/vsnprintf.texi
index 37923e1c7d..495647fac5 100644
--- a/doc/posix-functions/vsnprintf.texi
+++ b/doc/posix-functions/vsnprintf.texi
@@ -39,10 +39,6 @@ printf @code{"%f"}, @code{"%e"}, @code{"%g"} of Infinity and NaN yields an
 incorrect result on some platforms:
 AIX 5.2, OSF/1 5.1, Solaris 11 2011-11, mingw, MSVC 9.
 @item
-printf of @samp{long double} numbers outside the IEEE 754 range produces
-no meaningful results on some platforms:
-glibc and others, on x86, x86_64, IA-64 CPUs.
-@item
 This function does not support the @samp{a} and @samp{A} directives on some
 platforms:
 glibc-2.3.6, Mac OS X 10.5, NetBSD 5.0, OpenBSD 4.0, AIX 5.2, HP-UX 11,
@@ -96,6 +92,10 @@ HP-UX 11, OSF/1 5.1.
 Portability problems not fixed by Gnulib:
 @itemize
 @item
+Formatting noncanonical @samp{long double} numbers produces
+nonmeaningful results on some platforms:
+glibc and others, on x86, x86_64, IA-64 CPUs.
+@item
 When formatting an integer with grouping flag, this function inserts thousands
 separators even in the "C" locale on some platforms:
 NetBSD 5.1.
diff --git a/doc/posix-functions/vsprintf.texi b/doc/posix-functions/vsprintf.texi
index e329b6d26b..723e4d5010 100644
--- a/doc/posix-functions/vsprintf.texi
+++ b/doc/posix-functions/vsprintf.texi
@@ -20,10 +20,6 @@ printf @code{"%f"}, @code{"%e"}, @code{"%g"} of Infinity and NaN yields an
 incorrect result on some platforms:
 AIX 5.2, OSF/1 5.1, Solaris 11 2011-11, mingw, MSVC 9.
 @item
-printf of @samp{long double} numbers outside the IEEE 754 range produces
-no meaningful results on some platforms:
-glibc and others, on x86, x86_64, IA-64 CPUs.
-@item
 This function does not support the @samp{a} and @samp{A} directives on some
 platforms:
 glibc-2.3.6, Mac OS X 10.5, NetBSD 5.0, OpenBSD 4.0, AIX 5.2, HP-UX 11,
@@ -74,6 +70,10 @@ Mac OS X 10.3, FreeBSD 6.0, NetBSD 5.0.
 Portability problems not fixed by Gnulib:
 @itemize
 @item
+Formatting noncanonical @samp{long double} numbers produces
+nonmeaningful results on some platforms:
+glibc and others, on x86, x86_64, IA-64 CPUs.
+@item
 When formatting an integer with grouping flag, this function inserts thousands
 separators even in the "C" locale on some platforms:
 NetBSD 5.1.