RISC-V: Moved syscalls to separate files to fix aliasing problems.

libgloss/riscv/sys_sbrk.c

@@ -0,0 +1,27 @@
+#include <machine/syscall.h>
+#include <sys/types.h>
+#include "internal_syscall.h"
+
+/* Increase program data space. As malloc and related functions depend
+   on this, it is useful to have a working implementation. The following
+   is suggested by the newlib docs and suffices for a standalone
+   system.  */
+void *
+_sbrk(ptrdiff_t incr)
+{
+  static unsigned long heap_end;
+
+  if (heap_end == 0)
+    {
+      long brk = syscall_errno (SYS_brk, 0, 0, 0, 0, 0, 0);
+      if (brk == -1)
+	return (void *)-1;
+      heap_end = brk;
+    }
+
+  if (syscall_errno (SYS_brk, heap_end + incr, 0, 0, 0, 0, 0) != heap_end + incr)
+    return (void *)-1;
+
+  heap_end += incr;
+  return (void *)(heap_end - incr);
+}