Xcode 11 tools can't build CCL

[xrme]

The Xcode 11 developer tools can't build CCL. The problem seems to be regressions in the assembler.

Steps to reproduce:

cd lisp-kernel/darwinx8664
make clean
make
      ../x86-spentry64.s:1184:suffix or operands invalid for `movq'
      ../x86-spentry64.s:1184:4294967291 shortened to 251
      ../x86-spentry64.s:1190:suffix or operands invalid for `movq'
      ../x86-spentry64.s:1190:4294967291 shortened to 251
      ../x86-spentry64.s:1205:suffix or operands invalid for `movq'
      ../x86-spentry64.s:1205:4294967291 shortened to 251
      ../x86-spentry64.s:1211:suffix or operands invalid for `movq'

Bruce O'Neel made a small test case that shows the problem:

/* assemble with as -Q -g -arch x86_64 bus.s */
  
/* fails with assembler included with Xcode 11 -- Xcode 11.1.2 at least */

/* works on Xcode 10.3 or earler */

        node_size = 8
        dnode_size = 16
        num_subtag_bits = 8
        subtag_shift = num_subtag_bits
        ntagbits = 4
        fulltag_misc = 13
        misc_bias = fulltag_misc
        fulltag_nodeheader_0 = 5
        subtag_catch_frame = (fulltag_nodeheader_0 | (2 << ntagbits))
misc_header_offset = -fulltag_misc
misc_header_offset_neg = fulltag_misc
misc_data_offset = misc_header_offset+node_size /* first word of data    */
misc_subtag_offset = misc_header_offset       /* low byte of header   */

        .text
        .align 2
        .p2align 3

        .globl junk
junk:
        /* movq %rax,misc_data_offset(%rsi) */
        /* should all be the same */
        movq %rax,-5(%rsi)
        movq %rax,-13+8(%rsi)
        movq %rax,-13+node_size(%rsi)
        movq %rax,-fulltag_misc+node_size(%rsi)
        movq %rax,misc_header_offset_neg+node_size(%rsi)
        movq %rax,-misc_header_offset_neg+node_size(%rsi)
        movq %rax,node_size+misc_header_offset(%rsi)
        /* fails */
        movq %rax,misc_header_offset+node_size(%rsi)
        ret

I submitted a bug report to Apple on https://feedbackassistant.apple.com: FB7464217. Bruce submitted one also: FB7515029.

In the long term, CCL needs to change so that the LLVM assembler can be used, but this is a clear bug/regression in the older GNU assembler (which is what as -Q gives you).

As a workaround, you can install an earlier version of Xcode (such as 10.2). Move it to /Applications as Xcode-10.2.app (you can safely have multiple versions of Xcode installed), and select it with xcode-select -s /Applications/Xcode-10.2. The Xcode 10.2 tools can build the CCL lisp kernel.

[tomio-arisaka]

Xcode 11.3.1 assembler does not support the ccl assembly code.
But if you use MacPorts, you can assemble the ccl assembly code.
https://www.macports.org

$ sudo port install clang-9.0
$ sudo port install cctools

$ which as
/opt/local/bin/as
$ 
$ /opt/local/bin/as --version
clang version 9.0.1 
Target: x86_64-apple-darwin19.3.0
Thread model: posix
InstalledDir: /opt/local/libexec/llvm-9.0/bin
$ 

After that, you can build CCL on macOS Catalina 10.15.3.

[xrme]

Xcode 11.4 just came out. It appears to include a fixed assembler, because the included developer tools can now build CCL.

[easye]

Xcode 11.4 just came out. It appears to include a fixed assembler, because the included developer tools can now build CCL.

Xcode 11.4 doesn't support Mojave? A point release dropping support for the previous version of macOS? Very unhappy with AAPL…

[eschaton]

For much of the past decade, the spring release of Xcode is where support for running on the previous OS is dropped. There are significant technical reasons that things are this way and it happens every year so it shouldn’t be unexpected.