Adapt to more usual flags for ref_app

Author: ckormanyos

ref_app/target/app/make/app_make.gmk

@@ -265,7 +265,9 @@ GCCFLAGS    = -g                                \
               $(WARN_FLAGS)                     \
               -Wno-comment                      \
               -gdwarf-2                         \
-              -fno-exceptions
+              -fno-exceptions                   \
+              -fdata-sections                   \
+              -ffunction-sections
 
 CFLAGS      = $(GCCFLAGS)                       \
               $(TGT_CFLAGS)                     \

ref_app/target/micros/bl602_sifive_e24_riscv/Code/Appli/main.c

@@ -57,7 +57,7 @@
 //-----------------------------------------------------------------------------------------
 // Function Prototypes
 //-----------------------------------------------------------------------------------------
-void __attribute__((interrupt)) Isr_TIMER_Interrupt (void);
+void __attribute__((interrupt,used,noinline)) Isr_TIMER_Interrupt (void);
 
 //-----------------------------------------------------------------------------------------
 /// \brief  
@@ -66,6 +66,8 @@ void __attribute__((interrupt)) Isr_TIMER_Interrupt (void);
 ///
 /// \return 
 //-----------------------------------------------------------------------------------------
+int main(void) __attribute__((used,noinline));
+
 int main(void)
 {
   /* configure IO3 as output */

ref_app/target/micros/bl602_sifive_e24_riscv/Code/Startup/Startup.c

@@ -53,7 +53,7 @@ static void Startup_InitMcuSystem(void);
 //=========================================================================================
 // Extern function prototype
 //=========================================================================================
-int main(void) __attribute__((weak));
+int main(void) __attribute__((used,noinline));
 
 //-----------------------------------------------------------------------------------------
 /// \brief  Startup_Init function
@@ -62,6 +62,8 @@ int main(void) __attribute__((weak));
 ///
 /// \return void
 //-----------------------------------------------------------------------------------------
+void Startup_Init(void) __attribute__((used,noinline));
+
 void Startup_Init(void)
 {
   /* Initialize the MCU system */

ref_app/target/micros/bl602_sifive_e24_riscv/Code/Startup/intvect.c

@@ -27,7 +27,7 @@ static void UndefinedHandler(void);
 static void UndefinedHandler(void){ for(;;); }
 
 void Isr_SW_Interrupt      (void) __attribute__((weak, alias("UndefinedHandler")));
-void Isr_TIMER_Interrupt   (void) __attribute__((weak, alias("UndefinedHandler")));
+void Isr_TIMER_Interrupt   (void) __attribute__((interrupt,used,noinline));
 void Isr_Ext_Interrupt     (void) __attribute__((weak, alias("UndefinedHandler")));
 void Isr_CLIC_SW_Interrupt (void) __attribute__((weak, alias("UndefinedHandler")));
 void L1C_BMX_ERR           (void) __attribute__((weak, alias("UndefinedHandler")));
@@ -54,7 +54,7 @@ typedef void (*InterruptHandler)(void);
 //=====================================================================================================
 // Interrupt vector table
 //=====================================================================================================
-const InterruptHandler __attribute__((aligned(64))) InterruptVectorTable[] =
+const InterruptHandler __attribute__((aligned(64),section(".text.vivt"))) InterruptVectorTable[] =
 {
     (InterruptHandler)&UndefinedHandler,      /* IRQ 00  Reserved  */
     (InterruptHandler)&UndefinedHandler,      /* IRQ 01  Reserved  */

ref_app/target/micros/bl602_sifive_e24_riscv/make/bl602_sifive_e24_riscv_flags.gmk

@@ -44,11 +44,11 @@ TGT_INCLUDES := -I$(PATH_TGT)/Code                             \
                 -I$(PATH_TGT)/Code/StdLib/printf               \
                 -I$(PATH_TGT)/Code/StdLib
 
-TGT_AFLAGS    = $(ARCH)
+TGT_AFLAGS    = $(TGT_ALLFLAGS)
 
 TGT_LDFLAGS   = -nostdlib                                      \
                 -nostartfiles                                  \
-                -fno-lto                                       \
+                -Wl,--gc-sections                              \
                 -e _start                                      \
                 -Wl,-Map,$(APP).map                            \
                 -T $(LINKER_DEFINITION_FILE)