>From 9ad3c1032c3bac5f2e391c418324f26ee8abbe2d Mon Sep 17 00:00:00 2001
From: Eric Le Bihan <eric.le.bihan.dev@free.fr>
Date: Thu, 11 Aug 2016 19:57:09 +0200
Subject: [PATCH] configure: rework posix_spawn() detection

As uclibc-ng provides posix_spawn() in librt, rework the detection of
this function in the ./configure script to handle this situation.
---
 configure | 32 +++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/configure b/configure
index e4a1866..5320e41 100755
--- a/configure
+++ b/configure
@@ -450,6 +450,37 @@ EOF
     echo '  ... no'
   fi
 
+  echo "Checking whether system has posix_spawn()..."
+  hasposixspawn=true
+  if $CC_AUTO $CPPFLAGS_AUTO $CFLAGS_AUTO -c -o tryposixspawn.o src/sysdeps/tryposixspawn.c 2>/dev/null ; then
+    if $CC_AUTO $CFLAGS_AUTO $LDFLAGS_AUTO -o /dev/null tryposixspawn.o 2>/dev/null ; then
+      rt_lib=
+      echo "  ... yes"
+    elif $CC_AUTO $CFLAGS_AUTO $LDFLAGS_AUTO -o /dev/null tryposixspawn.o -lrt 2>/dev/null ; then
+      rt_lib=-lrt
+      echo "  ... yes, with -lrt"
+    else
+      hasposixspawn=false
+    fi
+    rm -f tryposixspawn.o
+  else
+     hasposixspawn=false
+  fi
+  if $hasposixspawn ; then
+    rm -f tryposixspawn
+    if test "$rt_lib" = "-lrt" ; then
+      if ! grep -q "\-lrt" $sysdeps/rt.lib; then
+        echo "-lrt" > $sysdeps/rt.lib
+      fi
+    fi
+    echo 'posixspawn: yes' >> $sysdeps/sysdeps
+    echo "#define ${package_macro_name}_HASPOSIXSPAWN" >> $sysdeps/sysdeps.h
+  else
+    echo 'posixspawn: no' >> $sysdeps/sysdeps
+    echo "#undef ${package_macro_name}_HASPOSIXSPAWN" >> $sysdeps/sysdeps.h
+    echo '  ... no'
+  fi
+
   echo "Checking system endianness..."
   $CC_AUTO $CPPFLAGS_AUTO $CFLAGS_AUTO -o tryendianness src/sysdeps/tryendianness.c
   endianness=$(./tryendianness) || fail "$0: unable to determine endianness"
@@ -480,7 +511,6 @@ EOF
   choose cl openat OPENAT 'openat()'
   choose cl linkat LINKAT 'linkat()'
   choose clr pipe2 PIPE2 'pipe2()'
-  choose cl posixspawn POSIXSPAWN 'posix_spawn()' $rt_lib
   choose clr ppoll PPOLL 'ppoll()'
   choose cl revoke REVOKE 'revoke()'
   choose cl sendfile SENDFILE 'sendfile()'
-- 
2.4.11