From 82ef0f70744ca47057b9e95cd926dbcb25ebb0c8 Mon Sep 17 00:00:00 2001
From: Joel Brobecker <brobecker@adacore.com>
Date: Fri, 6 Nov 2015 13:39:19 -0800
Subject: [PATCH] Do not use libiberty's getpagesize on Android

Building libiberty on Android currently fails with the error message
shown below.  This was discovered by trying to build GDBserver
for Android, which stopped building after libiberty became
a GDBserver dependency.

Here is the error message:

[...]/getpagesize.c:64:1: error: redefinition of 'getpagesize'
In file included from /[...]/getpagesize.c:34:0:
/[...]/usr/include/unistd.h:171:23: note: previous definition of 'getpagesize' was here

And looking at the definition, one can see that it defined as
a static inline function...

   static __inline__ int getpagesize(void) {
     extern unsigned int __page_size;
     return __page_size;
   }

... which explains why the AC_CHECK_FUNCS test failed to detect
the function, since there is no associated symbol to be linked in.

This patch prevents getpagesize.c to be compiled in by hard-coding
the fact that getpagesize is available on android hosts.

libiberty/ChangeLog:

        * configure.ac: Set AC_CV_FUNC_GETPAGESIZE to "yes" on
        Android hosts.
        * configure: Regenerate.
---
 libiberty/ChangeLog    | 6 ++++++
 libiberty/configure    | 6 ++++++
 libiberty/configure.ac | 6 ++++++
 3 files changed, 18 insertions(+)

diff --git a/libiberty/ChangeLog b/libiberty/ChangeLog
index 5b9a8cf2d9..0688ba8c58 100644
--- a/libiberty/ChangeLog
+++ b/libiberty/ChangeLog
@@ -1,3 +1,9 @@
+2015-11-06  Joel Brobecker  <brobecker@adacore.com>
+
+	* configure.ac: Set AC_CV_FUNC_GETPAGESIZE to "yes" on
+	Android hosts.
+	* configure: Regenerate.
+
 2015-09-30  Nick Clifton  <nickc@redhat.com>
 
 	Import the following patches from the GCC mainline:
diff --git a/libiberty/configure b/libiberty/configure
index d8890a11de..720dc5e80b 100755
--- a/libiberty/configure
+++ b/libiberty/configure
@@ -6248,6 +6248,12 @@ if test -z "${setobjs}"; then
 
   case "${host}" in
 
+  *-*-android*)
+    # On android, getpagesize is defined in unistd.h as a static inline
+    # function, which AC_CHECK_FUNCS does not handle properly.
+    ac_cv_func_getpagesize=yes
+    ;;
+
   *-*-mingw32*)
     # Under mingw32, sys_nerr and sys_errlist exist, but they are
     # macros, so the test below won't find them.
diff --git a/libiberty/configure.ac b/libiberty/configure.ac
index 868be8e72d..e21e3aa580 100644
--- a/libiberty/configure.ac
+++ b/libiberty/configure.ac
@@ -600,6 +600,12 @@ if test -z "${setobjs}"; then
 
   case "${host}" in
 
+  *-*-android*)
+    # On android, getpagesize is defined in unistd.h as a static inline
+    # function, which AC_CHECK_FUNCS does not handle properly.
+    ac_cv_func_getpagesize=yes
+    ;;
+
   *-*-mingw32*)
     # Under mingw32, sys_nerr and sys_errlist exist, but they are
     # macros, so the test below won't find them.