It is important that /usr/src/linux-...-obj/include is searched for
includes before /usr/src/linux-.../include so that the inclusion of
"include/linux/autoconf.h" picks up the one for the kernel we are
trying to build against, and not the one for the currently running
kernel, which is what is in /usr/src/linux-.../ copy is.
i=wangyb
i=cliff
AC_DEFUN([LB_LINUX_COMPILE_IFELSE],
[m4_ifvaln([$1], [AC_LANG_CONFTEST([$1])])dnl
rm -f build/conftest.o build/conftest.mod.c build/conftest.ko
-AS_IF([AC_TRY_COMMAND(cp conftest.c build && make -d [$2] ${LD:+"LD=$LD"} CC="$CC" -f $PWD/build/Makefile LUSTRE_LINUX_CONFIG=$LINUX_CONFIG LINUXINCLUDE="$EXTRA_LNET_INCLUDE -I$LINUX/arch/`uname -m|sed -e 's/ppc.*/powerpc/' -e 's/x86_64/x86/' -e 's/i.86/x86/'`/include -I$LINUX/include -I$LINUX_OBJ/include -I$LINUX_OBJ/include2 -include include/linux/autoconf.h" -o tmp_include_depends -o scripts -o include/config/MARKER -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM $MODULE_TARGET=$PWD/build) >/dev/null && AC_TRY_COMMAND([$3])],
+AS_IF([AC_TRY_COMMAND(cp conftest.c build && make -d [$2] ${LD:+"LD=$LD"} CC="$CC" -f $PWD/build/Makefile LUSTRE_LINUX_CONFIG=$LINUX_CONFIG LINUXINCLUDE="$EXTRA_LNET_INCLUDE -I$LINUX/arch/`uname -m|sed -e 's/ppc.*/powerpc/' -e 's/x86_64/x86/' -e 's/i.86/x86/'`/include -I$LINUX_OBJ/include -I$LINUX/include -I$LINUX_OBJ/include2 -include include/linux/autoconf.h" -o tmp_include_depends -o scripts -o include/config/MARKER -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM $MODULE_TARGET=$PWD/build) >/dev/null && AC_TRY_COMMAND([$3])],
[$4],
[_AC_MSG_LOG_CONFTEST
m4_ifvaln([$5],[$5])dnl])