No line number info in backtraces?

[dkegel-fastly]

Having line numbers would be handy, but they don't seem to be present. (And showing source code would be even nicer.)

$ cat bad.go
package main

func bad(a []int) {
        println(a[0])
}

func main() {
        bad([]int{})
}

$ tinygo build -opt 0 -o foo

$ lldb ./foo
(lldb) target create "./foo"
Current executable set to '/Users/dkegel/gr/foo' (x86_64).
(lldb) run
Process 14639 launched: '/Users/dkegel/gr/foo' (x86_64)
panic: runtime error: index out of range
Process 14639 stopped
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
    frame #0: 0x00007fff6d30633a libsystem_kernel.dylib`__pthread_kill + 10
libsystem_kernel.dylib`__pthread_kill:
->  0x7fff6d30633a <+10>: jae    0x7fff6d306344            ; <+20>
    0x7fff6d30633c <+12>: movq   %rax, %rdi
    0x7fff6d30633f <+15>: jmp    0x7fff6d300629            ; cerror_nocancel
    0x7fff6d306344 <+20>: retq
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
  * frame #0: 0x00007fff6d30633a libsystem_kernel.dylib`__pthread_kill + 10
    frame #1: 0x00007fff6d3c2e60 libsystem_pthread.dylib`pthread_kill + 430
    frame #2: 0x00007fff6d28d808 libsystem_c.dylib`abort + 120
    frame #3: 0x00000001000022a4 foo`runtime.runtimePanic + 52
    frame #4: 0x0000000100003032 foo`runtime.lookupPanic + 18
    frame #5: 0x0000000100003470 foo`main.bad + 32
    frame #6: 0x0000000100003496 foo`main.main + 22
    frame #7: 0x0000000100003210 foo`runtime.run$1 + 16
    frame #8: 0x00000001000031eb foo`runtime.run + 11
    frame #9: 0x00000001000031d6 foo`runtime.runMain + 6
    frame #10: 0x00000001000031b7 foo`main + 23
    frame #11: 0x00007fff6d1becc9 libdyld.dylib`start + 1
    frame #12: 0x00007fff6d1becc9 libdyld.dylib`start + 1
(lldb) f 5
frame #5: 0x0000000100003470 foo`main.bad + 32
foo`main.bad:
->  0x100003470 <+32>: ud2    
    0x100003472 <+34>: nopw   %cs:(%rax,%rax)
    0x10000347c <+44>: nopl   (%rax)

foo`main.main:
    0x100003480 <+0>:  pushq  %rax
(lldb) quit

This is with tinygo 0.17-ish on mac.

[aykevl]

TinyGo normally supports debug information, but apparently something is missing here. Weird.

I wonder if something is missing on MacOS? The last time I tried it worked just fine on Linux and other targets (using GDB).

[aykevl]

It appears to be working on Linux at least:

$ tinygo build -o test.elf ./testdata/alias.go
$ lldb-11 ./test.elf
(lldb) target create "./test.elf"
Current executable set to '/home/ayke/src/github.com/tinygo-org/tinygo/test.elf' (x86_64).
(lldb) b runtime.printnl 
Breakpoint 1: where = test.elf`runtime.printnl + 1 [inlined] runtime.putchar at print.go:286, address = 0x0000000000201751
(lldb) run
Process 22850 launched: '/home/ayke/src/github.com/tinygo-org/tinygo/test.elf' (x86_64)
Process 22850 stopped
* thread #1, name = 'test.elf', stop reason = breakpoint 1.1
    frame #0: 0x0000000000201751 test.elf`runtime.printnl [inlined] runtime.putchar(c='\r') at runtime_unix.go:66:10
   63  	}
   64  	
   65  	func putchar(c byte) {
-> 66  		_putchar(int(c))
   67  	}
   68  	
   69  	const asyncScheduler = false
(lldb) bt
* thread #1, name = 'test.elf', stop reason = breakpoint 1.1
  * frame #0: 0x0000000000201751 test.elf`runtime.printnl [inlined] runtime.putchar(c='\r') at runtime_unix.go:66:10
    frame #1: 0x0000000000201751 test.elf`runtime.printnl at print.go:286
    frame #2: 0x0000000000201788 test.elf`runtime.runMain [inlined] main.main at alias.go:29:9
    frame #3: 0x0000000000201774 test.elf`runtime.runMain [inlined] runtime.run$1 at scheduler_any.go:21
    frame #4: 0x0000000000201774 test.elf`runtime.runMain [inlined] runtime.run at scheduler_any.go:18
    frame #5: 0x0000000000201774 test.elf`runtime.runMain at runtime_unix.go:62
    frame #6: 0x000000000020176f test.elf`main at runtime_unix.go:53:9
    frame #7: 0x00007ffff7df909b libc.so.6`__libc_start_main(main=(test.elf`main at runtime_unix.go), argc=1, argv=0x00007fffffffe328, init=<unavailable>, fini=<unavailable>, rtld_fini=<unavailable>, stack_end=0x00007fffffffe318) at libc-start.c:308:16
    frame #8: 0x000000000020166a test.elf`_start + 42

Unfortunately I do not have access to a Mac so I can't reproduce your issue.

[dkegel-fastly]

Line numbers do work better on linux, thanks.

[aykevl]

I think I see why it doesn't work. In short: on MacOS, it seems that debug information is stored in object files and not in the final binary. TinyGo however creates an object file in a temporary directory and removes it after the build, so that object file (with debug information) is gone after compilation. Therefore lldb won't be able to find it.

I see two possible workarounds:

• Try installing GDB and use tinygo gdb <packagename>. It runs before the temporary directory is removed.
• Try running on a different target, for example -target=cortex-m-qemu. This is maybe not what you're after but might work in some cases.

For a proper fix, I intend to eventually move towards a non-LTO or ThinLTO compilation model which would keep object files in a cache and thus should allow regular debugging (as long as the cache isn't cleared with tinygo clean for example).

[aykevl]

Note to self: it appears to be more complicated than that (#2861 (comment)):

I did some digging to try and figure out why debug information isn't usable on darwin, and my theory is that it will be fixed with #2870. I suspect the issue is that something in the toolchain doesn't know how to deal with multiple compile units in a single file, which is exactly what TinyGo is doing.

Unfortunately, without proper debug information, fixing these bugs is a lot more complicated.

[aykevl]

Indeed, my suspicion was (almost) correct! Apart from fixing the multiple translation units in a single module, I also had to add llvm.ident which is a very small patch. More information: #3489 (comment)

[awmorgan]

@aykevl @dkegel-fastly I found that you have to run dsymutil to get the debug information created in foo.dSYM directory.

this is with 0.27.

observe:

/Volumes/git/foo $ tinygo version
tinygo version 0.27.0 darwin/amd64 (using go version go1.20.4 and LLVM version 15.0.0)
/Volumes/git/foo $ ls
go.mod  main.go
/Volumes/git/foo $ cat go.mod 
module foo

go 1.20
/Volumes/git/foo $ cat main.go 
package main

func bad(a []int) {
        println(a[0])
}

func main() {
        bad([]int{})
}
/Volumes/git/foo $ tinygo build -opt=0 .
/Volumes/git/foo $ lldb ./foo 
(lldb) target create "./foo"
Current executable set to '/Volumes/git/foo/foo' (x86_64).
(lldb) r
Process 45385 launched: '/Volumes/git/foo/foo' (x86_64)
panic: runtime error: index out of range
Process 45385 stopped
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
    frame #0: 0x00007fff2090290e libsystem_kernel.dylib`__pthread_kill + 10
libsystem_kernel.dylib`__pthread_kill:
->  0x7fff2090290e <+10>: jae    0x7fff20902918            ; <+20>
    0x7fff20902910 <+12>: movq   %rax, %rdi
    0x7fff20902913 <+15>: jmp    0x7fff208fcab9            ; cerror_nocancel
    0x7fff20902918 <+20>: retq   
Target 0: (foo) stopped.
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
  * frame #0: 0x00007fff2090290e libsystem_kernel.dylib`__pthread_kill + 10
    frame #1: 0x00007fff209315bd libsystem_pthread.dylib`pthread_kill + 263
    frame #2: 0x00007fff20886406 libsystem_c.dylib`abort + 125
    frame #3: 0x0000000100000e90 foo`runtime.runtimePanic(msg=<unavailable>) + 48 [opt]
    frame #4: 0x0000000100001882 foo`runtime.lookupPanic + 18 [opt]
    frame #5: 0x0000000100001eda foo`main.bad + 26
    frame #6: 0x0000000100001ef9 foo`main.main + 25 [opt]
    frame #7: 0x0000000100001e9b foo`runtime.run$1 + 11 [opt]
    frame #8: 0x0000000100001b46 foo`<goroutine wrapper> + 6 [opt]
    frame #9: 0x00000001000005f1 foo`tinygo_startTask at task_stack_amd64.S:29
(lldb) f 5
frame #5: 0x0000000100001eda foo`main.bad + 26
foo`main.bad:
->  0x100001eda <+26>: ud2    
    0x100001edc <+28>: nopl   (%rax)

foo`main.main:
    0x100001ee0 <+0>:  pushq  %rax
    0x100001ee1 <+1>:  movl   $0x3, %esi
(lldb) q
Quitting LLDB will kill one or more processes. Do you really want to proceed: [Y/n] Y
/Volumes/git/foo $ dsymutil  foo
/Volumes/git/foo $ lldb ./foo 
(lldb) target create "./foo"
Current executable set to '/Volumes/git/foo/foo' (x86_64).
(lldb) r
Process 45442 launched: '/Volumes/git/foo/foo' (x86_64)
panic: runtime error: index out of range
Process 45442 stopped
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
    frame #0: 0x00007fff2090290e libsystem_kernel.dylib`__pthread_kill + 10
libsystem_kernel.dylib`__pthread_kill:
->  0x7fff2090290e <+10>: jae    0x7fff20902918            ; <+20>
    0x7fff20902910 <+12>: movq   %rax, %rdi
    0x7fff20902913 <+15>: jmp    0x7fff208fcab9            ; cerror_nocancel
    0x7fff20902918 <+20>: retq   
Target 0: (foo) stopped.
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
  * frame #0: 0x00007fff2090290e libsystem_kernel.dylib`__pthread_kill + 10
    frame #1: 0x00007fff209315bd libsystem_pthread.dylib`pthread_kill + 263
    frame #2: 0x00007fff20886406 libsystem_c.dylib`abort + 125
    frame #3: 0x0000000100000e90 foo`runtime.runtimePanic(msg=<unavailable>) at panic.go:59:7 [opt]
    frame #4: 0x0000000100001882 foo`runtime.lookupPanic at panic.go:132:14 [opt]
    frame #5: 0x0000000100001eda foo`main.bad(a=<unavailable>) at main.go:4:11 [opt]
    frame #6: 0x0000000100001ef9 foo`main.main at main.go:8:5 [opt]
    frame #7: 0x0000000100001e9b foo`runtime.run$1 at scheduler_any.go:25:11 [opt]
    frame #8: 0x0000000100001b46 foo`<goroutine wrapper> at scheduler_any.go:23:2 [opt]
    frame #9: 0x00000001000005f1 foo`tinygo_startTask + 6
(lldb) f 5
foo was compiled with optimization - stepping may behave oddly; variables may not be available.
frame #5: 0x0000000100001eda foo`main.bad(a=<unavailable>) at main.go:4:11 [opt]
   1    package main
   2   
   3    func bad(a []int) {
-> 4            println(a[0])
   5    }
   6   
   7    func main() {
(lldb) q
Quitting LLDB will kill one or more processes. Do you really want to proceed: [Y/n] Y
/Volumes/git/foo $ 

[aykevl]

Have you tried the dev branch? #3491 should improve debug information on Darwin, but it's not included in TinyGo 0.27.0.

[awmorgan]

identical behavior is observed on the dev branch (commit: 7445741)

/Volumes/git/foo $ tinygo version
tinygo version 0.28.0-dev darwin/amd64 (using go version go1.20.4 and LLVM version 15.0.7)
/Volumes/git/foo $ tinygo build -opt=0 .
/Volumes/git/foo $ lldb ./foo
(lldb) target create "./foo"
Current executable set to '/Volumes/git/foo/foo' (x86_64).
(lldb) r
Process 49560 launched: '/Volumes/git/foo/foo' (x86_64)
panic: runtime error at 0x0000000100001d95: index out of range
Process 49560 stopped
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
    frame #0: 0x00007fff2090290e libsystem_kernel.dylib`__pthread_kill + 10
libsystem_kernel.dylib`__pthread_kill:
->  0x7fff2090290e <+10>: jae    0x7fff20902918            ; <+20>
    0x7fff20902910 <+12>: movq   %rax, %rdi
    0x7fff20902913 <+15>: jmp    0x7fff208fcab9            ; cerror_nocancel
    0x7fff20902918 <+20>: retq   
Target 0: (foo) stopped.
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
  * frame #0: 0x00007fff2090290e libsystem_kernel.dylib`__pthread_kill + 10
    frame #1: 0x00007fff209315bd libsystem_pthread.dylib`pthread_kill + 263
    frame #2: 0x00007fff20886406 libsystem_c.dylib`abort + 125
    frame #3: 0x0000000100000ca1 foo`runtime.runtimePanicAt(addr=<unavailable>, msg=<unavailable>) + 81 [opt]
    frame #4: 0x00000001000017b7 foo`runtime.lookupPanic + 23 [opt]
    frame #5: 0x0000000100001d9a foo`main.bad + 26
    frame #6: 0x0000000100001db9 foo`main.main + 25 [opt]
    frame #7: 0x0000000100001d5b foo`runtime.run$1 + 11 [opt]
    frame #8: 0x0000000100001a06 foo`<goroutine wrapper> + 6 [opt]
    frame #9: 0x0000000100000641 foo`tinygo_startTask at task_stack_amd64.S:29
(lldb) f 5
frame #5: 0x0000000100001d9a foo`main.bad + 26
foo`main.bad:
->  0x100001d9a <+26>: ud2    
    0x100001d9c <+28>: nopl   (%rax)

foo`main.main:
    0x100001da0 <+0>:  pushq  %rax
    0x100001da1 <+1>:  movl   $0x3, %esi
(lldb) q
Quitting LLDB will kill one or more processes. Do you really want to proceed: [Y/n] Y
/Volumes/git/foo $ dsymutil  foo
/Volumes/git/foo $ lldb ./foo
(lldb) target create "./foo"
Current executable set to '/Volumes/git/foo/foo' (x86_64).
(lldb) r
Process 49599 launched: '/Volumes/git/foo/foo' (x86_64)
panic: runtime error at 0x0000000100001d95: index out of range
Process 49599 stopped
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
    frame #0: 0x00007fff2090290e libsystem_kernel.dylib`__pthread_kill + 10
libsystem_kernel.dylib`__pthread_kill:
->  0x7fff2090290e <+10>: jae    0x7fff20902918            ; <+20>
    0x7fff20902910 <+12>: movq   %rax, %rdi
    0x7fff20902913 <+15>: jmp    0x7fff208fcab9            ; cerror_nocancel
    0x7fff20902918 <+20>: retq   
Target 0: (foo) stopped.
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
  * frame #0: 0x00007fff2090290e libsystem_kernel.dylib`__pthread_kill + 10
    frame #1: 0x00007fff209315bd libsystem_pthread.dylib`pthread_kill + 263
    frame #2: 0x00007fff20886406 libsystem_c.dylib`abort + 125
    frame #3: 0x0000000100000ca1 foo`runtime.runtimePanicAt(addr=<unavailable>, msg=<unavailable>) at panic.go:71:7 [opt]
    frame #4: 0x00000001000017b7 foo`runtime.lookupPanic at panic.go:144:16 [opt]
    frame #5: 0x0000000100001d9a foo`main.bad(a=<unavailable>) at main.go:4:11 [opt]
    frame #6: 0x0000000100001db9 foo`main.main at main.go:8:5 [opt]
    frame #7: 0x0000000100001d5b foo`runtime.run$1 at scheduler_any.go:25:11 [opt]
    frame #8: 0x0000000100001a06 foo`<goroutine wrapper> at scheduler_any.go:23:2 [opt]
    frame #9: 0x0000000100000641 foo`tinygo_startTask + 6
(lldb) f 5
foo was compiled with optimization - stepping may behave oddly; variables may not be available.
frame #5: 0x0000000100001d9a foo`main.bad(a=<unavailable>) at main.go:4:11 [opt]
   1    package main
   2   
   3    func bad(a []int) {
-> 4            println(a[0])
   5    }
   6   
   7    func main() {
(lldb) q
Quitting LLDB will kill one or more processes. Do you really want to proceed: [Y/n] Y
/Volumes/git/foo $ 

[aykevl]

Is it any better if you use tinygo gdb or tinygo lldb?

[awmorgan]

Below shows tinygo 0.27 and dev lldb and gdb. I don't see much difference in behavior. No line numbers in the backtrace without the .dSYM.

Overall gdb seems worse than lldb because there are no function names in backtrace with gdb

Also there is some issue with gdb where when you hit run, it hangs and you have to break into the program with ctrl+c.

tinygo lldb w/ 0.27

/Volumes/git/x $ tinygo version
tinygo version 0.27.0 darwin/amd64 (using go version go1.20.4 and LLVM version 15.0.0)
/Volumes/git/x $ rm ./x
rm: ./x: No such file or directory
/Volumes/git/x $ tinygo lldb -opt=0 .
(lldb) target create --arch=x86_64-apple-macosx10.12.0 "/var/folders/rp/fpc8t1293dn1r6jycrqn0hlw0000gn/T/tinygo3827229396/main"
Current executable set to '/var/folders/rp/fpc8t1293dn1r6jycrqn0hlw0000gn/T/tinygo3827229396/main' (x86_64).
(lldb) r
Process 83474 launched: '/var/folders/rp/fpc8t1293dn1r6jycrqn0hlw0000gn/T/tinygo3827229396/main' (x86_64)
panic: runtime error: index out of range
Process 83474 stopped
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
    frame #0: 0x00007fff2090290e libsystem_kernel.dylib`__pthread_kill + 10
libsystem_kernel.dylib`__pthread_kill:
->  0x7fff2090290e <+10>: jae    0x7fff20902918            ; <+20>
    0x7fff20902910 <+12>: movq   %rax, %rdi
    0x7fff20902913 <+15>: jmp    0x7fff208fcab9            ; cerror_nocancel
    0x7fff20902918 <+20>: retq   
Target 0: (main) stopped.
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
  * frame #0: 0x00007fff2090290e libsystem_kernel.dylib`__pthread_kill + 10
    frame #1: 0x00007fff209315bd libsystem_pthread.dylib`pthread_kill + 263
    frame #2: 0x00007fff20886406 libsystem_c.dylib`abort + 125
    frame #3: 0x0000000100000e90 main`runtime.runtimePanic(msg=<unavailable>) + 48 [opt]
    frame #4: 0x0000000100001882 main`runtime.lookupPanic + 18 [opt]
    frame #5: 0x0000000100001eda main`main.bad + 26
    frame #6: 0x0000000100001ef9 main`main.main + 25 [opt]
    frame #7: 0x0000000100001e9b main`runtime.run$1 + 11 [opt]
    frame #8: 0x0000000100001b46 main`<goroutine wrapper> + 6 [opt]
    frame #9: 0x00000001000005f1 main`tinygo_startTask at task_stack_amd64.S:29
(lldb) f5
error: 'f5' is not a valid command.
(lldb) f 5
frame #5: 0x0000000100001eda main`main.bad + 26
main`main.bad:
->  0x100001eda <+26>: ud2    
    0x100001edc <+28>: nopl   (%rax)

main`main.main:
    0x100001ee0 <+0>:  pushq  %rax
    0x100001ee1 <+1>:  movl   $0x3, %esi
(lldb) q
Quitting LLDB will kill one or more processes. Do you really want to proceed: [Y/n] Y 
/Volumes/git/x $ 

tinygo dev branch

/Volumes/git/x $ rm ./x
rm: ./x: No such file or directory
/Volumes/git/x $ ls
go.mod  main.go
/Volumes/git/x $ tinygo version
tinygo version 0.28.0-dev darwin/amd64 (using go version go1.20.4 and LLVM version 15.0.7)
/Volumes/git/x $ tinygo lldb -opt=0 .
(lldb) target create --arch=x86_64-apple-macosx10.12.0 "/var/folders/rp/fpc8t1293dn1r6jycrqn0hlw0000gn/T/tinygo2252565719/main"
Current executable set to '/var/folders/rp/fpc8t1293dn1r6jycrqn0hlw0000gn/T/tinygo2252565719/main' (x86_64).
(lldb) r
Process 83647 launched: '/var/folders/rp/fpc8t1293dn1r6jycrqn0hlw0000gn/T/tinygo2252565719/main' (x86_64)
panic: runtime error at 0x0000000100001d95: index out of range
Process 83647 stopped
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
    frame #0: 0x00007fff2090290e libsystem_kernel.dylib`__pthread_kill + 10
libsystem_kernel.dylib`__pthread_kill:
->  0x7fff2090290e <+10>: jae    0x7fff20902918            ; <+20>
    0x7fff20902910 <+12>: movq   %rax, %rdi
    0x7fff20902913 <+15>: jmp    0x7fff208fcab9            ; cerror_nocancel
    0x7fff20902918 <+20>: retq   
Target 0: (main) stopped.
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGABRT
  * frame #0: 0x00007fff2090290e libsystem_kernel.dylib`__pthread_kill + 10
    frame #1: 0x00007fff209315bd libsystem_pthread.dylib`pthread_kill + 263
    frame #2: 0x00007fff20886406 libsystem_c.dylib`abort + 125
    frame #3: 0x0000000100000ca1 main`runtime.runtimePanicAt(addr=<unavailable>, msg=<unavailable>) + 81 [opt]
    frame #4: 0x00000001000017b7 main`runtime.lookupPanic + 23 [opt]
    frame #5: 0x0000000100001d9a main`main.bad + 26
    frame #6: 0x0000000100001db9 main`main.main + 25 [opt]
    frame #7: 0x0000000100001d5b main`runtime.run$1 + 11 [opt]
    frame #8: 0x0000000100001a06 main`<goroutine wrapper> + 6 [opt]
    frame #9: 0x0000000100000641 main`tinygo_startTask at task_stack_amd64.S:29
(lldb) f 5
frame #5: 0x0000000100001d9a main`main.bad + 26
main`main.bad:
->  0x100001d9a <+26>: ud2    
    0x100001d9c <+28>: nopl   (%rax)

main`main.main:
    0x100001da0 <+0>:  pushq  %rax
    0x100001da1 <+1>:  movl   $0x3, %esi
(lldb) q
Quitting LLDB will kill one or more processes. Do you really want to proceed: [Y/n] Y
/Volumes/git/x $ 

tinygo gdb 0.27

/Volumes/git/x $ tinygo version
tinygo version 0.27.0 darwin/amd64 (using go version go1.20.4 and LLVM version 15.0.0)
/Volumes/git/x $ tinygo gdb -opt=0 .
GNU gdb (GDB) 13.2
Copyright (C) 2023 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "x86_64-apple-darwin20.6.0".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from /var/folders/rp/fpc8t1293dn1r6jycrqn0hlw0000gn/T/tinygo1134386546/main...

warning: can't find symbol 'tinygo_longjmp' in minsymtab

warning: `/Users/billmorgan/Library/Caches/tinygo/thinlto/llvmcache-61D9010EEEF97DF1AF5D11CB93452909465FEA9A': file time stamp mismatch.
(gdb) r
Starting program: /private/var/folders/rp/fpc8t1293dn1r6jycrqn0hlw0000gn/T/tinygo1134386546/main 
[New Thread 0x2803 of process 83807]
^C[New Thread 0x1c03 of process 83807]
warning: unhandled dyld version (17)
panic: runtime error: index out of range

Thread 2 received signal SIGABRT, Aborted.
0x00007fff2090290e in ?? ()
(gdb) bt
#0  0x00007fff2090290e in ?? ()
#1  0x00007fff209315bd in ?? ()
#2  0x0000000000000003 in ?? ()
#3  0x0000000100001b40 in runtime[run] ()
#4  0x00000001000e0e00 in ?? ()
#5  0x000000010100ffa8 in ?? ()
#6  0x000000010100ffd0 in ?? ()
#7  0x00007fff20886406 in ?? ()
#8  0x00007fff208ff02e in ?? ()
#9  0x00000000fffff9df in ?? ()
#10 0xffffffff01010570 in ?? ()
#11 0x000000010000207e in runtime$string ()
#12 0x0000000000000012 in ?? ()
#13 0x0000000000000000 in ?? ()
(gdb) f 5
#5  0x000000010100ffa8 in ?? ()
(gdb) q
A debugging session is active.

        Inferior 1 [process 83807] will be killed.

Quit anyway? (y or n) y
/Volumes/git/x $ 

tinygo gdb dev branch

/Volumes/git/x $ tinygo version
tinygo version 0.28.0-dev darwin/amd64 (using go version go1.20.4 and LLVM version 15.0.7)
/Volumes/git/x $ tinygo gdb -opt=0 .
GNU gdb (GDB) 13.2
Copyright (C) 2023 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "x86_64-apple-darwin20.6.0".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://www.gnu.org/software/gdb/bugs/>.
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    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from /var/folders/rp/fpc8t1293dn1r6jycrqn0hlw0000gn/T/tinygo3061731878/main...

warning: can't find symbol 'tinygo_longjmp' in minsymtab

warning: `/Users/billmorgan/Library/Caches/tinygo/thinlto/llvmcache-A963352A034D43859B1FA88B07DA8C16146EFB2B': file time stamp mismatch.
(gdb) r
Starting program: /private/var/folders/rp/fpc8t1293dn1r6jycrqn0hlw0000gn/T/tinygo3061731878/main 
[New Thread 0x1903 of process 83974]
^C[New Thread 0x2503 of process 83974]
warning: unhandled dyld version (17)
panic: runtime error at 0x0000000100001d95: index out of range

Thread 2 received signal SIGABRT, Aborted.
0x00007fff2090290e in ?? ()
(gdb) bt
#0  0x00007fff2090290e in ?? ()
#1  0x00007fff209315bd in ?? ()
#2  0x0000000000000003 in ?? ()
#3  0x0000000100001a00 in ?? ()
#4  0x00000001000dfe00 in ?? ()
#5  0x000000010100ffa8 in ?? ()
#6  0x000000010100ffd0 in ?? ()
#7  0x00007fff20886406 in ?? ()
#8  0x00007fff208ff02e in ?? ()
#9  0x00000000fffff9df in ?? ()
#10 0xffffffff01010830 in ?? ()
#11 0x0000000100001d95 in ?? ()
#12 0x0000000000000012 in ?? ()
#13 0x0000000100001ec3 in runtime$string ()
#14 0x0000000000000000 in ?? ()
(gdb) q
A debugging session is active.

        Inferior 1 [process 83974] will be killed.

Quit anyway? (y or n) y
/Volumes/git/x $ 

[aykevl]

I assume this will eventually be solved once we implement real ThinLTO support (instead of our custom LTO setup). See #3489 (it will take a while until this is ready for merge).