diff --git a/02_runtime_init/Cargo.toml b/02_runtime_init/Cargo.toml
index ef7d6d86..da487f1a 100644
--- a/02_runtime_init/Cargo.toml
+++ b/02_runtime_init/Cargo.toml
@@ -13,4 +13,4 @@ default = []
 bsp_rpi3 = []
 
 [dependencies]
-r0 = "0.2.2"
+r0 = "0.2.*"
diff --git a/02_runtime_init/README.md b/02_runtime_init/README.md
index f0139dc9..5d588cfb 100644
--- a/02_runtime_init/README.md
+++ b/02_runtime_init/README.md
@@ -19,46 +19,46 @@ We are calling into Rust code for the first time.
 ```diff
 
 diff -uNr 01_wait_forever/Cargo.toml 02_runtime_init/Cargo.toml
---- 01_wait_forever/Cargo.toml	2019-09-23 15:09:10.919233495 +0200
-+++ 02_runtime_init/Cargo.toml	2019-09-23 15:10:15.775036819 +0200
+--- 01_wait_forever/Cargo.toml
++++ 02_runtime_init/Cargo.toml
 @@ -13,4 +13,4 @@
  bsp_rpi3 = []
 
  [dependencies]
 -
-+r0 = "0.2.2"
++r0 = "0.2.*"
 
 diff -uNr 01_wait_forever/src/bsp/rpi3/link.ld 02_runtime_init/src/bsp/rpi3/link.ld
---- 01_wait_forever/src/bsp/rpi3/link.ld	2019-09-23 15:09:10.919233495 +0200
-+++ 02_runtime_init/src/bsp/rpi3/link.ld	2019-09-23 15:10:15.767036845 +0200
+--- 01_wait_forever/src/bsp/rpi3/link.ld
++++ 02_runtime_init/src/bsp/rpi3/link.ld
 @@ -13,5 +13,23 @@
-         *(.text)
+         *(.text._start) *(.text*)
      }
 
 +    .rodata :
 +    {
-+        *(.rodata)
++        *(.rodata*)
 +    }
 +
 +    .data :
 +    {
-+        *(.data)
++        *(.data*)
 +    }
 +
 +    /* Align to 8 byte boundary */
 +    .bss ALIGN(8):
 +    {
 +        __bss_start = .;
-+        *(.bss);
++        *(.bss*);
 +        __bss_end = .;
 +    }
 +
-     /DISCARD/ : { *(.comment) }
+     /DISCARD/ : { *(.comment*) }
  }
 
 diff -uNr 01_wait_forever/src/bsp/rpi3/start.S 02_runtime_init/src/bsp/rpi3/start.S
---- 01_wait_forever/src/bsp/rpi3/start.S	2019-09-23 15:09:10.919233495 +0200
-+++ 02_runtime_init/src/bsp/rpi3/start.S	2019-09-23 15:10:15.767036845 +0200
+--- 01_wait_forever/src/bsp/rpi3/start.S
++++ 02_runtime_init/src/bsp/rpi3/start.S
 @@ -7,5 +7,15 @@
  .global _start
 
@@ -79,8 +79,8 @@ diff -uNr 01_wait_forever/src/bsp/rpi3/start.S 02_runtime_init/src/bsp/rpi3/star
 +                            // park this core aswell
 
 diff -uNr 01_wait_forever/src/main.rs 02_runtime_init/src/main.rs
---- 01_wait_forever/src/main.rs	2019-09-24 22:57:44.947372097 +0200
-+++ 02_runtime_init/src/main.rs	2019-09-24 22:57:32.811412514 +0200
+--- 01_wait_forever/src/main.rs
++++ 02_runtime_init/src/main.rs
 @@ -16,4 +16,11 @@
  // `_start()` function, the first function to run.
  mod bsp;
@@ -96,8 +96,8 @@ diff -uNr 01_wait_forever/src/main.rs 02_runtime_init/src/main.rs
 +}
 
 diff -uNr 01_wait_forever/src/runtime_init.rs 02_runtime_init/src/runtime_init.rs
---- 01_wait_forever/src/runtime_init.rs	1970-01-01 01:00:00.000000000 +0100
-+++ 02_runtime_init/src/runtime_init.rs	2019-09-24 22:32:25.569243801 +0200
+--- 01_wait_forever/src/runtime_init.rs
++++ 02_runtime_init/src/runtime_init.rs
 @@ -0,0 +1,27 @@
 +// SPDX-License-Identifier: MIT
 +//
diff --git a/03_hacky_hello_world/Cargo.toml b/03_hacky_hello_world/Cargo.toml
index ef7d6d86..da487f1a 100644
--- a/03_hacky_hello_world/Cargo.toml
+++ b/03_hacky_hello_world/Cargo.toml
@@ -13,4 +13,4 @@ default = []
 bsp_rpi3 = []
 
 [dependencies]
-r0 = "0.2.2"
+r0 = "0.2.*"
diff --git a/03_hacky_hello_world/README.md b/03_hacky_hello_world/README.md
index 72096033..1773905a 100644
--- a/03_hacky_hello_world/README.md
+++ b/03_hacky_hello_world/README.md
@@ -15,8 +15,8 @@ enabled step-by-step in following tutorials.
 ```diff
 
 diff -uNr 02_runtime_init/Makefile 03_hacky_hello_world/Makefile
---- 02_runtime_init/Makefile	2019-09-23 15:10:43.906916928 +0200
-+++ 03_hacky_hello_world/Makefile	2019-09-23 15:11:53.602555646 +0200
+--- 02_runtime_init/Makefile
++++ 03_hacky_hello_world/Makefile
 @@ -13,7 +13,7 @@
  	OUTPUT = kernel8.img
  	QEMU_BINARY = qemu-system-aarch64
@@ -24,12 +24,12 @@ diff -uNr 02_runtime_init/Makefile 03_hacky_hello_world/Makefile
 -	QEMU_MISC_ARGS = -d in_asm
 +	QEMU_MISC_ARGS = -serial null -serial stdio
  	LINKER_FILE = src/bsp/rpi3/link.ld
- 	RUSTC_MISC_ARGS = -C target-feature=-fp-armv8 -C target-cpu=cortex-a53
+ 	RUSTC_MISC_ARGS = -C target-cpu=cortex-a53
  endif
 
 diff -uNr 02_runtime_init/src/bsp/rpi3/panic_wait.rs 03_hacky_hello_world/src/bsp/rpi3/panic_wait.rs
---- 02_runtime_init/src/bsp/rpi3/panic_wait.rs	2019-09-23 15:10:15.767036845 +0200
-+++ 03_hacky_hello_world/src/bsp/rpi3/panic_wait.rs	2019-09-24 00:48:21.431980264 +0200
+--- 02_runtime_init/src/bsp/rpi3/panic_wait.rs
++++ 03_hacky_hello_world/src/bsp/rpi3/panic_wait.rs
 @@ -4,10 +4,17 @@
 
  //! A panic handler that infinitely waits.
@@ -51,8 +51,8 @@ diff -uNr 02_runtime_init/src/bsp/rpi3/panic_wait.rs 03_hacky_hello_world/src/bs
              asm!("wfe" :::: "volatile")
 
 diff -uNr 02_runtime_init/src/bsp/rpi3.rs 03_hacky_hello_world/src/bsp/rpi3.rs
---- 02_runtime_init/src/bsp/rpi3.rs	2019-09-23 15:10:15.767036845 +0200
-+++ 03_hacky_hello_world/src/bsp/rpi3.rs	2019-09-24 22:34:35.220657927 +0200
+--- 02_runtime_init/src/bsp/rpi3.rs
++++ 03_hacky_hello_world/src/bsp/rpi3.rs
 @@ -6,4 +6,38 @@
 
  mod panic_wait;
@@ -94,8 +94,8 @@ diff -uNr 02_runtime_init/src/bsp/rpi3.rs 03_hacky_hello_world/src/bsp/rpi3.rs
 +}
 
 diff -uNr 02_runtime_init/src/interface.rs 03_hacky_hello_world/src/interface.rs
---- 02_runtime_init/src/interface.rs	1970-01-01 01:00:00.000000000 +0100
-+++ 03_hacky_hello_world/src/interface.rs	2019-09-24 22:35:18.288465568 +0200
+--- 02_runtime_init/src/interface.rs
++++ 03_hacky_hello_world/src/interface.rs
 @@ -0,0 +1,36 @@
 +// SPDX-License-Identifier: MIT
 +//
@@ -135,8 +135,8 @@ diff -uNr 02_runtime_init/src/interface.rs 03_hacky_hello_world/src/interface.rs
 +}
 
 diff -uNr 02_runtime_init/src/main.rs 03_hacky_hello_world/src/main.rs
---- 02_runtime_init/src/main.rs	2019-09-24 22:57:32.811412514 +0200
-+++ 03_hacky_hello_world/src/main.rs	2019-09-24 22:56:54.635538411 +0200
+--- 02_runtime_init/src/main.rs
++++ 03_hacky_hello_world/src/main.rs
 @@ -6,9 +6,17 @@
  #![doc(html_logo_url = "https://git.io/JeGIp")]
 
@@ -171,8 +171,8 @@ diff -uNr 02_runtime_init/src/main.rs 03_hacky_hello_world/src/main.rs
  }
 
 diff -uNr 02_runtime_init/src/print.rs 03_hacky_hello_world/src/print.rs
---- 02_runtime_init/src/print.rs	1970-01-01 01:00:00.000000000 +0100
-+++ 03_hacky_hello_world/src/print.rs	2019-09-24 22:30:10.489867506 +0200
+--- 02_runtime_init/src/print.rs
++++ 03_hacky_hello_world/src/print.rs
 @@ -0,0 +1,32 @@
 +// SPDX-License-Identifier: MIT
 +//
diff --git a/04_zero_overhead_abstraction/Cargo.toml b/04_zero_overhead_abstraction/Cargo.toml
index 85b3a052..a0734bd3 100644
--- a/04_zero_overhead_abstraction/Cargo.toml
+++ b/04_zero_overhead_abstraction/Cargo.toml
@@ -10,8 +10,10 @@ sysroot_path = "../xbuild_sysroot"
 # The features section is used to select the target board.
 [features]
 default = []
-bsp_rpi3 = []
+bsp_rpi3 = ["cortex-a"]
 
 [dependencies]
-r0 = "0.2.2"
-cortex-a = "2.7.0"
+r0 = "0.2.*"
+
+# Optional dependencies
+cortex-a = { version = "2.*", optional = true }
diff --git a/04_zero_overhead_abstraction/README.md b/04_zero_overhead_abstraction/README.md
index b5dd1077..c18d7d19 100644
--- a/04_zero_overhead_abstraction/README.md
+++ b/04_zero_overhead_abstraction/README.md
@@ -11,17 +11,24 @@ which provides zero-overhead abstractions and wraps the `unsafe` parts.
 ```diff
 
 diff -uNr 03_hacky_hello_world/Cargo.toml 04_zero_overhead_abstraction/Cargo.toml
---- 03_hacky_hello_world/Cargo.toml	2019-09-25 14:41:51.089487788 +0200
-+++ 04_zero_overhead_abstraction/Cargo.toml	2019-09-25 13:59:33.588482692 +0200
-@@ -14,3 +14,4 @@
+--- 03_hacky_hello_world/Cargo.toml
++++ 04_zero_overhead_abstraction/Cargo.toml
+@@ -10,7 +10,10 @@
+ # The features section is used to select the target board.
+ [features]
+ default = []
+-bsp_rpi3 = []
++bsp_rpi3 = ["cortex-a"]
 
  [dependencies]
- r0 = "0.2.2"
-+cortex-a = "2.7.0"
+ r0 = "0.2.*"
++
++# Optional dependencies
++cortex-a = { version = "2.*", optional = true }
 
 diff -uNr 03_hacky_hello_world/src/bsp/rpi3/panic_wait.rs 04_zero_overhead_abstraction/src/bsp/rpi3/panic_wait.rs
---- 03_hacky_hello_world/src/bsp/rpi3/panic_wait.rs	2019-09-25 14:41:51.093487759 +0200
-+++ 04_zero_overhead_abstraction/src/bsp/rpi3/panic_wait.rs	2019-09-25 15:26:48.988205284 +0200
+--- 03_hacky_hello_world/src/bsp/rpi3/panic_wait.rs
++++ 04_zero_overhead_abstraction/src/bsp/rpi3/panic_wait.rs
 @@ -6,6 +6,7 @@
 
  use crate::println;
@@ -44,8 +51,8 @@ diff -uNr 03_hacky_hello_world/src/bsp/rpi3/panic_wait.rs 04_zero_overhead_abstr
  }
 
 diff -uNr 03_hacky_hello_world/src/bsp/rpi3/start.S 04_zero_overhead_abstraction/src/bsp/rpi3/start.S
---- 03_hacky_hello_world/src/bsp/rpi3/start.S	2019-09-25 15:07:28.593140386 +0200
-+++ 04_zero_overhead_abstraction/src/bsp/rpi3/start.S	1970-01-01 01:00:00.000000000 +0100
+--- 03_hacky_hello_world/src/bsp/rpi3/start.S
++++ 04_zero_overhead_abstraction/src/bsp/rpi3/start.S
 @@ -1,21 +0,0 @@
 -// SPDX-License-Identifier: MIT
 -//
@@ -70,8 +77,8 @@ diff -uNr 03_hacky_hello_world/src/bsp/rpi3/start.S 04_zero_overhead_abstraction
 -                            // park this core aswell
 
 diff -uNr 03_hacky_hello_world/src/bsp/rpi3.rs 04_zero_overhead_abstraction/src/bsp/rpi3.rs
---- 03_hacky_hello_world/src/bsp/rpi3.rs	2019-09-25 14:41:51.093487759 +0200
-+++ 04_zero_overhead_abstraction/src/bsp/rpi3.rs	2019-09-25 15:19:14.474175689 +0200
+--- 03_hacky_hello_world/src/bsp/rpi3.rs
++++ 04_zero_overhead_abstraction/src/bsp/rpi3.rs
 @@ -8,8 +8,34 @@
 
  use crate::interface::console;
@@ -110,8 +117,8 @@ diff -uNr 03_hacky_hello_world/src/bsp/rpi3.rs 04_zero_overhead_abstraction/src/
  struct QEMUOutput;
 
 diff -uNr 03_hacky_hello_world/src/main.rs 04_zero_overhead_abstraction/src/main.rs
---- 03_hacky_hello_world/src/main.rs	2019-09-25 14:41:52.341478676 +0200
-+++ 04_zero_overhead_abstraction/src/main.rs	2019-09-25 15:22:45.433268740 +0200
+--- 03_hacky_hello_world/src/main.rs
++++ 04_zero_overhead_abstraction/src/main.rs
 @@ -13,9 +13,7 @@
  //!
  //! [`kernel::interface`]: interface/index.html
@@ -133,8 +140,8 @@ diff -uNr 03_hacky_hello_world/src/main.rs 04_zero_overhead_abstraction/src/main
  }
 
 diff -uNr 03_hacky_hello_world/src/runtime_init.rs 04_zero_overhead_abstraction/src/runtime_init.rs
---- 03_hacky_hello_world/src/runtime_init.rs	2019-09-25 14:41:51.093487759 +0200
-+++ 04_zero_overhead_abstraction/src/runtime_init.rs	2019-09-25 14:00:32.560262587 +0200
+--- 03_hacky_hello_world/src/runtime_init.rs
++++ 04_zero_overhead_abstraction/src/runtime_init.rs
 @@ -13,7 +13,7 @@
  ///
  /// - Only a single core must be active and running this function.
diff --git a/04_zero_overhead_abstraction/kernel b/04_zero_overhead_abstraction/kernel
index 04f2c470..90056506 100755
Binary files a/04_zero_overhead_abstraction/kernel and b/04_zero_overhead_abstraction/kernel differ
diff --git a/04_zero_overhead_abstraction/kernel8.img b/04_zero_overhead_abstraction/kernel8.img
index 37798266..761489e8 100755
Binary files a/04_zero_overhead_abstraction/kernel8.img and b/04_zero_overhead_abstraction/kernel8.img differ
diff --git a/utils/diff_tut_folders.bash b/utils/diff_tut_folders.bash
index b9f28119..4d44a5b9 100755
--- a/utils/diff_tut_folders.bash
+++ b/utils/diff_tut_folders.bash
@@ -7,7 +7,8 @@ DIFF=$(
 	 -x kernel8.img \
 	 -x Cargo.lock \
 	 -x target \
-	 $1 $2
+	 $1 $2 \
+        | sed -r "s/[12][90][127][90]-.*//g"
      )
 
 printf "\n\n## Diff to previous\n" >> "$2/README.md"