Added explicit discard list for clang compiler

Author: danielinux

arch.mk

@@ -1299,7 +1299,9 @@ ifeq ($(USE_CLANG),1)
   CFLAGS+=-isystem $(CLANG_NEWLIB_INCLUDE)
   CFLAGS+=-DWOLFSSL_NO_ATOMIC -DWOLFSSL_NO_ATOMICS
   CFLAGS+=-Wno-unknown-attributes -Wno-error=unknown-attributes
+  CFLAGS+=-fno-unwind-tables -fno-asynchronous-unwind-tables
   LDFLAGS+=-nostdlib
+  LSCRIPT_FLAGS+=-T hal/clang-discard.ld
 endif
 
 ifeq ($(USE_GCC),1)

hal/clang-discard.ld

@@ -0,0 +1,14 @@
+SECTIONS
+{
+    /DISCARD/ :
+    {
+        *(.ARM.extab* .gnu.linkonce.armextab.*)
+        *(.eh_frame* .gcc_except_table*)
+        *(.preinit_array*)
+        *(.init_array*)
+        *(.fini_array*)
+        *(.ctors*)
+        *(.dtors*)
+        *(.jcr*)
+    }
+}

hal/stm32l4.ld

@@ -15,6 +15,7 @@ SECTIONS
         . = ALIGN(4);
         _end_text = .;
     } > FLASH
+
     .edidx :
     {
         . = ALIGN(4);

test-app/Makefile

@@ -109,6 +109,7 @@ ifeq ($(USE_CLANG),1)
   # objcopy output then expands the flash-to-RAM gap into a huge sparse image.
   # The app image only needs the flash-backed output sections.
   OBJCOPY_IMAGE_FLAGS+=-j .text -j .edidx
+  LDFLAGS+=-T ../hal/clang-discard.ld
 endif
 
 ifeq ($(DEBUG_UART),1)