sandbox: eliminate unused functions from binaries
The sandbox should closely mimic other architectures.
Place each function or data in a separate section and let the linker
eliminate unused ones. This will reduce the binary size.
In the linker script mark that u_boot_sandbox_getopt are to be kept.
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/sandbox/config.mk b/arch/sandbox/config.mk
index 2d184c5..1d50991 100644
--- a/arch/sandbox/config.mk
+++ b/arch/sandbox/config.mk
@@ -2,7 +2,7 @@
# Copyright (c) 2011 The Chromium OS Authors.
PLATFORM_CPPFLAGS += -D__SANDBOX__ -U_FORTIFY_SOURCE
-PLATFORM_CPPFLAGS += -fPIC
+PLATFORM_CPPFLAGS += -fPIC -ffunction-sections -fdata-sections
PLATFORM_LIBS += -lrt
SDL_CONFIG ?= sdl2-config
@@ -30,7 +30,7 @@
$(u-boot-main) \
$(u-boot-keep-syms-lto) \
-Wl,--no-whole-archive \
- $(PLATFORM_LIBS) -Wl,-Map -Wl,u-boot.map
+ $(PLATFORM_LIBS) -Wl,-Map -Wl,u-boot.map -Wl,--gc-sections
cmd_u-boot-spl = (cd $(obj) && $(CC) -o $(SPL_BIN) -Wl,-T u-boot-spl.lds \
$(KBUILD_LDFLAGS:%=-Wl,%) \
diff --git a/arch/sandbox/cpu/u-boot.lds b/arch/sandbox/cpu/u-boot.lds
index ba8dee5..52f13af 100644
--- a/arch/sandbox/cpu/u-boot.lds
+++ b/arch/sandbox/cpu/u-boot.lds
@@ -15,7 +15,7 @@
_u_boot_sandbox_getopt : {
*(_u_boot_sandbox_getopt_start)
- *(_u_boot_sandbox_getopt)
+ KEEP(*(_u_boot_sandbox_getopt))
*(_u_boot_sandbox_getopt_end)
}