add riscv32 nix cross-toolchain and fibonacci c file

2 files changed, 15 insertions, 0 deletions

diff --git a/fibonacci.c b/fibonacci.c
new file mode 100644
index 0000000..8ba9225
--- /dev/null
+++ b/fibonacci.c
@@ -0,0 +1,13 @@
+void
+_start()
+{
+  int *fib0 = 0, *fib1 = 1;
+
+  *fib0 = 0;
+  *fib1 = 1;
+
+  for (int *fibx = 2; *fibx <= 15; fibx++)
+    *fibx = *(fibx - 1) + *(fibx - 2);
+
+  while (1);
+}
diff --git a/shell.nix b/shell.nix
new file mode 100644
index 0000000..bf86c40
--- /dev/null
+++ b/shell.nix
@@ -0,0 +1,2 @@
+with import <nixpkgs> {};
+pkgsCross.riscv32-embedded.mkShell {}