Hi,

coreutils has recently started to use strtold() [1]. This causes compilation
errors on Android 4.3:

  CC       lib/cl-strtod.o
  CC       lib/cl-strtold.o
In file included from ../lib/cl-strtold.c:2:
../lib/cl-strtod.c: In function 'cl_strtold':
../lib/cl-strtod.c:62: warning: implicit declaration of function 'strtold'

  CCLD     src/printf
lib/libcoreutils.a(cl-strtold.o): In function `cl_strtold':
cl-strtold.c:(.text+0x14): undefined reference to `strtold'
collect2: ld returned 1 exit status
make[2]: *** [src/printf] Error 1

  CCLD     src/seq
lib/libcoreutils.a(cl-strtold.o): In function `cl_strtold':
cl-strtold.c:(.text+0x14): undefined reference to `strtold'
collect2: ld returned 1 exit status
make[2]: *** [src/seq] Error 1

and similarly on Solaris 9 (both lack the strtold() function)
and on HP-UX 11/hppa (where the function is declared to return a struct,
not a 'long double').

And of course the function is not POSIX compliant on some platforms.

Here comes a new gnulib module 'strtold'. Tested on

- a glibc 2.3.2 system (Fedora 1)
- Mac OS X 10.5, Mac OS X 10.4/PowerPC
- FreeBSD 11.0
- NetBSD 7.1
- OpenBSD 6.0
- Minix 3.3
- AIX 7.1
- HP-UX 11.31/hppa
- HP-UX 11.31/ia64 (test failure in line 574, also in test-strtod.c:574)
- IRIX 6.5
- Solaris 9/SPARC, Solaris 10/SPARC, Solaris 10/x86
- Cygwin
- mingw
- Haiku
- Android 4.3

Bruno

[1] https://git.savannah.gnu.org/gitweb/?p=coreutils.git;a=commitdiff;h=eb73e23f31f4ce363b1505cc77424832d5c39063


2019-01-29  Bruno Haible  <bruno@clisp.org>

	strtold: New module.
	* lib/stdlib.in.h (strtold): New declaration.
	* lib/strtold.c: New file.
	* lib/strtod.c: Consider USE_LONG_DOUBLE.
	(STRTOD, LDEXP, HAVE_UNDERLYING_STRTOD, DOUBLE, MIN, MAX, L_,
	USE_LDEXP): New macros.
	(LDEXP, scale_radix_exp, parse_number, STRTOD): Adapt for
	USE_LONG_DOUBLE.
	(underlying_strtod): Remove function. Replace with some macros.
	Re-add the code for a missing underlying function that was removed on
	2013-02-19.
	* m4/strtold.m4: New file.
	* m4/stdlib_h.m4 (gl_STDLIB_H): Test whether strtold is declared.
	(gl_STDLIB_H_DEFAULTS): Initialize GNULIB_STRTOLD, HAVE_STRTOLD,
	REPLACE_STRTOLD.
	* modules/stdlib (Makefile.am): Substitute GNULIB_STRTOLD, HAVE_STRTOLD,
	REPLACE_STRTOLD.
	* modules/strtold: New file.
	* doc/posix-functions/strtold.texi: Document the new module.

2019-01-29  Bruno Haible  <bruno@clisp.org>

	strtold: Add tests.
	* tests/test-strtold.c: New file, based on tests/test-strtod.c.
	* modules/strtold-tests: New file.