getpass: Fix compilation error on Android

getpass: Fix compilation error on Android

[Bruno Haible]

On Android, I'm seeing this compilation error:

clang -DHAVE_CONFIG_H -DEXEEXT=\"\" -DEXEEXT=\"\" -DNO_XMALLOC -DEXEEXT=\"\" -I. -I../../gllib -I..  -DGNULIB_STRICT_CHECKING=1 -I/data/data/com.termux/files/home/local/include -Wall -fvisibility=hidden -O2 -c -o getpass.o ../../gllib/getpass.c
../../gllib/getpass.c:85:1: error: redefinition of 'getpass'
getpass (const char *prompt)
^
/data/data/com.termux/files/usr/include/unistd.h:419:25: note: previous definition is here
static __inline__ char* getpass(const char* prompt) {
                        ^
1 error generated.
make[3]: *** [Makefile:10690: getpass.o] Error 1

The cause is that Android's <unistd.h> defines getpass() as an inline function.
This should better be avoided.


2023-01-05  Bruno Haible  <bruno@clisp.org>

	getpass: Fix compilation error on Android.
	* m4/getpass.m4 (gl_FUNC_GETPASS): Define NO_INLINE_GETPASS.
	* doc/glibc-functions/getpass.texi: Mention the Android problem.

diff --git a/doc/glibc-functions/getpass.texi b/doc/glibc-functions/getpass.texi
index 17f1b2374b..8d2ff847ee 100644
--- a/doc/glibc-functions/getpass.texi
+++ b/doc/glibc-functions/getpass.texi
@@ -22,6 +22,10 @@ Portability problems fixed by either Gnulib module @code{getpass} or @code{getpa
 @item
 This function is missing on some platforms:
 mingw, MSVC 14, Android 9.0.
+@item
+This function cannot be called from plain inline or extern inline functions
+on some platforms:
+Android 13.
 @end itemize
 
 Portability problems fixed by Gnulib module @code{getpass-gnu}:
diff --git a/m4/getpass.m4 b/m4/getpass.m4
index 15882712d9..2dce1e0dfe 100644
--- a/m4/getpass.m4
+++ b/m4/getpass.m4
@@ -1,4 +1,4 @@
-# getpass.m4 serial 17
+# getpass.m4 serial 18
 dnl Copyright (C) 2002-2003, 2005-2006, 2009-2023 Free Software Foundation,
 dnl Inc.
 dnl This file is free software; the Free Software Foundation
@@ -13,6 +13,9 @@ AC_DEFUN_ONCE([gl_FUNC_GETPASS],
   dnl Persuade Solaris <unistd.h> and <stdlib.h> to declare getpass().
   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
 
+  dnl Persuade Android <unistd.h> to not define getpass() as an inline function.
+  AC_DEFINE([NO_INLINE_GETPASS], [1], [Define to 1 on Android.])
+
   AC_CHECK_FUNCS_ONCE([getpass])
   if test $ac_cv_func_getpass = no; then
     HAVE_GETPASS=0