poky-tiny: enable section removal

Use GCC sections flags so that unused sections can be garbage
collected at link time.

(From meta-yocto rev: 70176ee6235c2545e18df855cac2c3524b7e50e4)

Signed-off-by: Sinan Kaya <okaya@kernel.org>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta-poky/conf/distro/include/gcsections.inc

@@ -0,0 +1,22 @@
+CFLAGS_SECTION_REMOVAL = "-ffunction-sections -fdata-sections"
+LDFLAGS_SECTION_REMOVAL = "-Wl,--gc-sections"
+
+# packages with build problems using sections
+CFLAGS_SECTION_REMOVAL_pn-glibc = ""
+LDFLAGS_SECTION_REMOVAL_pn-glibc = ""
+CFLAGS_SECTION_REMOVAL_pn-cairo = ""
+LDFLAGS_SECTION_REMOVAL_pn-cairo = ""
+CFLAGS_SECTION_REMOVAL_pn-perl = ""
+LDFLAGS_SECTION_REMOVAL_pn-perl = ""
+CFLAGS_SECTION_REMOVAL_pn-grub-efi = ""
+LDFLAGS_SECTION_REMOVAL_pn-grub-efi = ""
+CFLAGS_SECTION_REMOVAL_pn-grub = ""
+LDFLAGS_SECTION_REMOVAL_pn-grub = ""
+
+# set default for target
+CFLAGS_append_class-target = " ${CFLAGS_SECTION_REMOVAL}"
+LDFLAGS_append_class-target = " ${LDFLAGS_SECTION_REMOVAL}"
+
+# set default for nativesdk
+CFLAGS_append_class-nativesdk = " ${CFLAGS_SECTION_REMOVAL}"
+LDFLAGS_append_class-nativesdk = " ${LDFLAGS_SECTION_REMOVAL}"

meta-poky/conf/distro/poky-tiny.conf

@@ -29,6 +29,8 @@
 # [ ] Modify busybox to allow for DISTRO_FEATURES-like confiruration
 
 require conf/distro/poky.conf
+require conf/distro/include/gcsections.inc
+
 DISTRO = "poky-tiny"
 DISTROOVERRIDES = "poky:poky-tiny"
 TCLIBC = "musl"