armv7: add -funwind-tables compile option to support stacktrace

Change-Id: Icfa223397e05dcd42ea3c12275385104bf275213
Signed-off-by: Joseph Chen <[email protected]>

Author: JosephChen2017

arch/arm/config.mk

@@ -139,7 +139,8 @@ OBJCOPYFLAGS += -j .text -j .secure_text -j .secure_data -j .rodata -j .data \
 		-j .u_boot_list -j .rela.dyn -j .got -j .got.plt
 else
 OBJCOPYFLAGS += -j .text -j .secure_text -j .secure_data -j .rodata -j .hash \
-		-j .data -j .got -j .got.plt -j .u_boot_list -j .rel.dyn
+		-j .data -j .got -j .got.plt -j .u_boot_list -j .rel.dyn \
+		-j .ARM.exidx -j .ARM.extab
 endif
 
 # if a dtb section exists we always have to include it

arch/arm/cpu/armv7/config.mk

@@ -11,3 +11,7 @@
 # of our decision.
 PF_NO_UNALIGNED := $(call cc-option, -mno-unaligned-access,)
 PLATFORM_CPPFLAGS += $(PF_NO_UNALIGNED)
+
+ifeq ($(CONFIG_SPL_BUILD)$(CONFIG_TPL_BUILD),)
+PLATFORM_CPPFLAGS += -mabi=aapcs-linux -funwind-tables
+endif

examples/Makefile

@@ -8,6 +8,10 @@ ifdef FTRACE
 subdir-ccflags-y += -finstrument-functions -DFTRACE
 endif
 
+# Here is an compile issue: "undefined reference to `__aeabi_unwind_cpp_pr0'..."
+# when -funwind-tables is enabled, so make it compile depends on -funwind-tables.
+ifeq (,$(findstring -funwind-tables,$(PLATFORM_CPPFLAGS)))
 subdir-y += standalone
 subdir-$(CONFIG_API) += api
 endif
+endif