gcc __attribute__((constructor)): Remove hacked calling, move ctor sections to flash

More hacky moving of parts of .rodata to flash, until we can move all of
it.

Candidate fix for #128

FreeRTOS/Source/portable/esp8266/port.c

@@ -178,9 +178,6 @@ void xPortSysTickHandle (void)
 	//OpenNMI();
 }
 
-static bool sdk_compat_initialised;
-void sdk_compat_initialise(void);
-
 /*
  * See header file for description.
  */
@@ -189,14 +186,6 @@ portBASE_TYPE xPortStartScheduler( void )
     _xt_isr_attach(INUM_SOFT, SV_ISR);
     _xt_isr_unmask(BIT(INUM_SOFT));
 
-    /* ENORMOUS HACK: Call the sdk_compat_initialise() function.
-       This can be removed happily once we have open source startup code.
-    */
-    if(!sdk_compat_initialised) {
-        sdk_compat_initialised = true;
-        sdk_compat_initialise();
-    }
-
     /* Initialize system tick timer interrupt and schedule the first tick. */
     _xt_isr_attach(INUM_TICK, sdk__xt_timer_int);
     _xt_isr_unmask(BIT(INUM_TICK));

core/app_main.c

@@ -407,6 +407,9 @@ void sdk_user_init_task(void *params) {
     vTaskDelete(NULL);
 }
 
+extern void (*__init_array_start)(void);
+extern void (*__init_array_end)(void);
+
 // .Lfunc009 -- .irom0.text+0x5b4
 static void user_start_phase2(void) {
     uint8_t *buf;
@@ -437,6 +440,12 @@ static void user_start_phase2(void) {
     uart_flush_txfifo(0);
     uart_flush_txfifo(1);
 
+    // Call gcc constructor functions
+    void (**ctor)(void);
+    for ( ctor = &__init_array_start; ctor != &__init_array_end; ++ctor) {
+        (*ctor)();
+    }
+
     if (phy_info[0] != 5) {
         // Bad version byte.  Discard what we read and use default values
         // instead.

core/sdk_compat.c

@@ -17,20 +17,6 @@ void IRAM *zalloc(size_t nbytes)
     return calloc(1, nbytes);
 }
 
-extern void (*__init_array_start)(void);
-extern void (*__init_array_end)(void);
-
-/* Do things which should be done as part of the SDK startup code, but aren't.
-   TODO: Move into app_main.c
-*/
-void sdk_compat_initialise()
-{
-    /* Call C++ constructors or C functions marked with __attribute__((constructor)) */
-    void (**p)(void);
-    for ( p = &__init_array_start; p != &__init_array_end; ++p)
-        (*p)();
-}
-
 /* UART RX function from Espressif SDK internals.
  *
  * Not part of published API.

ld/common.ld

@@ -139,13 +139,34 @@ SECTIONS
        (except for libgcc which is matched above.)
     */
     *(.literal .text .literal.* .text.*)
+    /* Anything explicitly marked as "irom" or "irom0" should go here */
+    *(.irom.* .irom.*.* .irom0.*)
+    _irom0_text_end = ABSOLUTE(.);
+
+    /* Temporary .rodata hacks start here, eventually all rodata will
+    be in irom by default */
     /* mbedtls rodata */
     *mbedtls.a:*.o(.rodata.* .rodata)
     /* actual certificate in example (TEMPORARY HACK) */
     *:cert.o(.rodata.* .rodata)
-    /* Anything explicitly marked as "irom" or "irom0" should go here */
-    *(.irom.* .irom.*.* .irom0.*)
-    _irom0_text_end = ABSOLUTE(.);
+    /*  C++ constructor and destructor tables, properly ordered:  */
+    __init_array_start = ABSOLUTE(.);
+    KEEP (*crtbegin.o(.ctors))
+    KEEP (*(EXCLUDE_FILE (*crtend.o) .ctors))
+    KEEP (*(SORT(.ctors.*)))
+    KEEP (*(.ctors))
+    __init_array_end = ABSOLUTE(.);
+    KEEP (*crtbegin.o(.dtors))
+    KEEP (*(EXCLUDE_FILE (*crtend.o) .dtors))
+    KEEP (*(SORT(.dtors.*)))
+    KEEP (*(.dtors))
+    /*  C++ exception handlers table:  */
+    __XT_EXCEPTION_DESCS__ = ABSOLUTE(.);
+    *(.xt_except_desc)
+    *(.gnu.linkonce.h.*)
+    __XT_EXCEPTION_DESCS_END__ = ABSOLUTE(.);
+    *(.xt_except_desc_end)
+
   } >irom0_0_seg :irom0_0_phdr
 
   .data : ALIGN(4)
@@ -179,23 +200,6 @@ SECTIONS
     *(.gnu.version_r)
     *(.eh_frame)
     . = (. + 3) & ~ 3;
-    /*  C++ constructor and destructor tables, properly ordered:  */
-    __init_array_start = ABSOLUTE(.);
-    KEEP (*crtbegin.o(.ctors))
-    KEEP (*(EXCLUDE_FILE (*crtend.o) .ctors))
-    KEEP (*(SORT(.ctors.*)))
-    KEEP (*(.ctors))
-    __init_array_end = ABSOLUTE(.);
-    KEEP (*crtbegin.o(.dtors))
-    KEEP (*(EXCLUDE_FILE (*crtend.o) .dtors))
-    KEEP (*(SORT(.dtors.*)))
-    KEEP (*(.dtors))
-    /*  C++ exception handlers table:  */
-    __XT_EXCEPTION_DESCS__ = ABSOLUTE(.);
-    *(.xt_except_desc)
-    *(.gnu.linkonce.h.*)
-    __XT_EXCEPTION_DESCS_END__ = ABSOLUTE(.);
-    *(.xt_except_desc_end)
     *(.dynamic)
     *(.gnu.version_d)
     . = ALIGN(4);		/* this table MUST be 4-byte aligned */
@@ -230,7 +234,6 @@ SECTIONS
   } >dram0_0_seg :dram0_0_bss_phdr
 /* __stack = 0x3ffc8000; */
 
-
   .lit4 : ALIGN(4)
   {
     _lit4_start = ABSOLUTE(.);