Can you replicate the examples on macOS?

[japaric]

Let us know if you had to significantly deviate from the instructions!

[tekjar]

I can do this

[japaric]

@tekjar Thanks! To clarify: do you mean you can run the examples on macOS? Or that you would test this (but haven't yet)?

[tekjar]

Oops. Sorry for the confusion. Yet to test.

[odunboye]

@japaric I have tested the example in Memory layout page and got the follow error :

error: language item required, but not found: `eh_personality`
error: aborting due to previous error
error: Could not compile `app`.
To learn more, run the command again with --verbose.

What could be the issue?
Thanks .

[japaric]

@odunboye sounds like you are compiling the program for the host instead of cross compiling. Did you set up a default build target in .cargo/config as covered in the last part of the first section (smallest std program)? If you missed it, it may be good to mention it again in the second section.

[odunboye]

@japaric I was able to compile it by setting the .cargo/config content
Currently testing the rest of the examples on MacOS
Thanks

[odunboye]

@japaric I was able to test the example up until the very last one where I can't generate the "release" version of the output like target/thumbv7m-none-eabi/release/app but was able to compile to the debug output.
What compilation flag compiles for the release version?

[andre-richter]

Try using the --release argument when building.

Note to self: add this missing info to the book.

[twilco]

I ran through the whole thing (almost) without issue on MacOS 10.12.6.

I did run into issues with the lldb related stuff, but it seems to be Python problems. From the end of the "Memory layout" section:

$ lldb target/thumbv7m-none-eabi/debug/embedonomicon
(lldb) target create "target/thumbv7m-none-eabi/debug/embedonomicon"
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "/usr/local/Cellar/python@2/2.7.15_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/copy.py", line 52, in <module>
    import weakref
  File "/usr/local/Cellar/python@2/2.7.15_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/weakref.py", line 14, in <module>
    from _weakref import (
ImportError: cannot import name _remove_dead_weakref
Current executable set to 'target/thumbv7m-none-eabi/debug/embedonomicon' (arm).
(lldb) gdb-remote 3333
Process 1 stopped
* thread #1, stop reason = signal SIGTRAP
    frame #0: 0x00000008 embedonomicon`Reset at main.rs:9
   6    
   7    #[panic_handler]
   8    fn panic(_panic: &PanicInfo) -> ! {
-> 9        loop {}
   10   }
   11   
   12   // The reset handler
Target 0: (embedonomicon) stopped.
(lldb) disassemble -frame
embedonomicon`Reset:
->  0x8 <+0>:  sub    sp, #0x4
    0xa <+2>:  movs   r0, #0x2a
    0xc <+4>:  str    r0, [sp]
    0xe <+6>:  b      0x10                      ; <+8> at main.rs:18
    0x10 <+8>: b      0x10                      ; <+8> at main.rs:18
(lldb) print/x $sp
error: need to add support for DW_TAG_base_type '!' encoded with DW_ATE = 0x7, bit_size = 0
(unsigned int) $0 = 0x20010000
(lldb) step
Process 1 stopped
* thread #1, stop reason = step in
    frame #0: 0x0000000c embedonomicon`Reset at main.rs:15
   12   // The reset handler
   13   #[no_mangle]
   14   pub unsafe extern "C" fn Reset() -> ! {
-> 15       let _x = 42;
   16   
   17       // can't return so we go into an infinite loop here
   18       loop {}
Target 0: (embedonomicon) stopped.
(lldb) step
Process 1 stopped
* thread #1, stop reason = step in
    frame #0: 0x0000000e embedonomicon`Reset at main.rs:18
   15       let _x = 42;
   16   
   17       // can't return so we go into an infinite loop here
-> 18       loop {}
   19   }
   20   
   21   // The reset vector, a pointer into the reset handler
Target 0: (embedonomicon) stopped.

However, things mostly worked :). Looking at flutter/flutter#17803, there is probably some brew/Python finagling that could be done to make it work.

Might be worth noting in the embedonomicon that installing QEMU and qemu-system-arm on MacOS is as simple as brew install qemu. Googling "install qemu macos" and/or "install qemu-system-arm macos" doesn't yield a lot of clear information to get what is needed only for this guide (and not QEMU for emulating a Raspberry Pi or something else, which I saw a lot of).

[japaric]

@twilco thanks for the report. Some windows users are also having trouble with lldb so I think we'll recommend gdb instead of lldb.

Might be worth noting in the embedonomicon that installing QEMU and qemu-system-arm on MacOS is as simple as brew install qemu

Thanks for the info! I'll add a small section to the preface covering how to install the tools on macOS.