Set --nmagic to avoid weirdness, and skip entry u32.

Author: jonathanpallant

samples/.cargo/config.toml

@@ -1,11 +1,11 @@
 [target.thumbv7em-none-eabihf]
-rustflags = ["-C", "link-arg=-Tneotron-cortex-m.ld"]
+rustflags = ["-C", "link-arg=-Tneotron-cortex-m.ld"] # , "-C", "link-arg=--nmagic"]
 
 [target.thumbv7em-none-eabi]
-rustflags = ["-C", "link-arg=-Tneotron-cortex-m.ld"]
+rustflags = ["-C", "link-arg=-Tneotron-cortex-m.ld"] # , "-C", "link-arg=--nmagic"]
 
 [target.thumbv7m-none-eabi]
-rustflags = ["-C", "link-arg=-Tneotron-cortex-m.ld"]
+rustflags = ["-C", "link-arg=-Tneotron-cortex-m.ld"] # , "-C", "link-arg=--nmagic"]
 
 [target.thumbv6m-none-eabi]
-rustflags = ["-C", "link-arg=-Tneotron-cortex-m.ld"]
+rustflags = ["-C", "link-arg=-Tneotron-cortex-m.ld"] # , "-C", "link-arg=--nmagic"]

samples/neotron-cortex-m.ld

@@ -25,42 +25,28 @@ ENTRY(app_entry);
 /* # Sections */
 SECTIONS
 {
-
-  /* ### .entry_point */
-  .entry_point ORIGIN(RAM) :
-  {
-      KEEP(*(.entry_point))
-  } > RAM
-
-  PROVIDE(_stext = ADDR(.entry_point) + SIZEOF(.entry_point));
-
   /* ### .text */
-  .text _stext :
+  .text : ALIGN(4)
   {
+    . = ALIGN(4);
     *(.text .text.*);
-    *(.HardFaultTrampoline);
-    *(.HardFault.*);
+    . = ALIGN(4);
   }
 
   /* ### .rodata */
   .rodata : ALIGN(4)
   {
+    . = ALIGN(4);
     *(.rodata .rodata.*);
-
-    /* 4-byte align the end (VMA) of this section.
-       This is required by LLD to ensure the LMA of the following .data
-       section will have the correct alignment. */
     . = ALIGN(4);
   }
 
   /* ### .data */
   .data : ALIGN(4)
   {
     . = ALIGN(4);
-    __sdata = .;
     *(.data .data.*);
-    . = ALIGN(4); /* 4-byte align the end (VMA) of this section */
-    __edata = .;
+    . = ALIGN(4);
   }
 
   /* LMA of .data */
@@ -70,10 +56,8 @@ SECTIONS
   .bss : ALIGN(4)
   {
     . = ALIGN(4);
-    __sbss = .;
     *(.bss .bss.*);
-    . = ALIGN(4); /* 4-byte align the end (VMA) of this section */
-    __ebss = .;
+    . = ALIGN(4);
   }
 
   /* ### .uninit */
@@ -84,10 +68,6 @@ SECTIONS
     . = ALIGN(4);
   }
 
-  /* Place the heap right after `.uninit` */
-  . = ALIGN(4);
-  __sheap = .;
-
   /* ## .got */
   /* Dynamic relocations are unsupported. This section is only used to detect relocatable code in
      the input files and raise an error if relocatable code is found */

src/lib.rs

@@ -36,10 +36,6 @@ extern "C" {
 // Static Variables
 // ============================================================================
 
-#[link_section = ".entry_point"]
-#[used]
-pub static APP_ENTRY: AppStartFn = app_entry;
-
 /// Holds a pointer to the OS API provided by the OS on start-up.
 ///
 /// Once you've hit the application `main()`, this will be non-null.
@@ -257,6 +253,7 @@ impl Drop for ReadDir {
 ///
 /// Will jump to the application entry point, and `extern "C"` function
 /// called `main`.
+#[no_mangle]
 extern "C" fn app_entry(api: *mut Api) -> i32 {
     API.store(api, Ordering::Relaxed);
     unsafe { neotron_main() }