Merge pull request #253 from ia0/fix

Make sure .heap is 4-byte aligned

Author: romancardenas

riscv-rt/CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Changed
 
+- Ensure the `.heap` section is 4-byte aligned
 - Limit rustc cfg flags to `riscvi`, `riscvm`, `riscvf`, and `riscvd`.
 - Temporary use of `RISCV_RT_LLVM_ARCH_PATCH` environment variable to include the
   temporary patch required for avoid LLVM spurious errors.

riscv-rt/link.x.in

@@ -168,7 +168,7 @@ SECTIONS
   __ebss = .;
 
   /* fictitious region that represents the memory available for the heap */
-  .heap (NOLOAD) :
+  .heap (NOLOAD) : ALIGN(4)
   {
     __sheap = .;
     . += _heap_size;