Sets -Wno-error=address-of-packed-member built with GCC9

See also frugalos#10.

install_deps.sh

@@ -39,11 +39,9 @@ cd ../
 git clone https://github.com/openstack/liberasurecode.git
 cd liberasurecode/
 git checkout 1.5.0
-if [ "$(uname)" == "Darwin" ]; then
-    # if the compiler has the feature to check `address-of-packed-member`, we suppress it.
-    # it is only annoying for liberasurecode v1.5.0.
-    patch -p1 < ../for_darwin_to_detect_compiler_flag.patch
-fi
+# if the compiler has the feature to check `address-of-packed-member`, we suppress it.
+# it is only annoying for liberasurecode v1.5.0.
+patch -p1 < ../jerasure.patch
 ./autogen.sh
 CFLAGS="-I${BUILD_DIR}/jerasure/include -I${BUILD_DIR}/include"
 CFLAGS=$CFLAGS LIBS="-lJerasure" LDFLAGS="-L${BUILD_DIR}/lib" ./configure --disable-shared --with-pic --prefix $BUILD_DIR

jerasure.patch

@@ -0,0 +1,23 @@
+--- a/configure.ac	2019-04-19 16:27:52.000000000 +0900
++++ b/configure.ac	2019-04-19 16:26:06.000000000 +0900
+@@ -39,6 +39,20 @@ AC_PROG_LN_S
+ dnl Compiling with per-target flags requires AM_PROG_CC_C_O.
+ AC_PROG_CC
+ AM_PROG_CC_C_O
++
++# Check if a compiler supports "-Wno-error=address-of-packed-member"
++# If it supports the option, we add it to CFLAGS.
++ac_save_CFLAGS="$CFLAGS"
++AC_LANG_PUSH([C])
++CFLAGS="-Wno-error=address-of-packed-member"
++AC_COMPILE_IFELSE([AC_LANG_PROGRAM([],[[]])],
++[ac_c_recognize_address_of_packed_member=1],
++[ac_c_recognize_address_of_packed_member=0])
++AC_LANG_POP([C])
++AS_IF([test $ac_c_recognize_address_of_packed_member -eq 1],
++[CFLAGS="$ac_save_CFLAGS -Wno-error=address-of-packed-member"],
++[CFLAGS="$ac_save_CFLAGS"])
++
+ AC_PROG_LIBTOOL
+ AC_PROG_CXX
+ AC_PROG_INSTALL