LinearLifetimeCheckerPrivate.h: Error! Found a leaked owned value that was never consumed.

[tayloraswift]

Description

the horror

Reproduction

func f(x:[Int]?)
{
}
func g()
{
    let x:[Int]? = nil
    return f(x: consume x)
}

Stack dump

Begin Error in Function: '$s4main1gyyF'
Error! Found a leaked owned value that was never consumed.
Value:   %2 = move_value [allows_diagnostics] %0 : $Optional<Array<Int>> // user: %4
End Error in Function: '$s4main1gyyF'
Found ownership error?!
triggering standard assertion failure routine
UNREACHABLE executed at /home/build-user/swift/lib/SIL/Verifier/LinearLifetimeCheckerPrivate.h:211!
Stack dump:
0.      Program arguments: /usr/bin/swift-frontend -frontend -interpret - -disable-objc-interop -I swiftfiddle.com/_Packages/.build/release -new-driver-path /usr/bin/swift-driver -empty-abi-descriptor -resource-dir /usr/lib/swift -module-name main -plugin-path /usr/lib/swift/host/plugins -plugin-path /usr/local/lib/swift/host/plugins -l_Packages
1.      Swift version 5.10-dev (LLVM dbfaba0078e9380, Swift 63c8b551eb2f613)
2.      Compiling with the current language version
3.      While evaluating request ASTLoweringRequest(Lowering AST to SIL for module main)
4.      While silgen emitFunction SIL function "@$s4main1gyyF".
 for 'g()' (at <stdin>:5:1)
5.      While verifying SIL function "@$s4main1gyyF".
 for 'g()' (at <stdin>:5:1)
Stack dump without symbol names (ensure you have llvm-symbolizer in your PATH or set the environment var `LLVM_SYMBOLIZER_PATH` to point to it):
/usr/bin/swift-frontend(+0x7307d73)[0x55ab79230d73]
/usr/bin/swift-frontend(+0x7305abe)[0x55ab7922eabe]
/usr/bin/swift-frontend(+0x73080ea)[0x55ab792310ea]
/lib/x86_64-linux-gnu/libc.so.6(+0x42520)[0x7fdbbb03e520]
/lib/x86_64-linux-gnu/libc.so.6(pthread_kill+0x12c)[0x7fdbbb0929fc]
/lib/x86_64-linux-gnu/libc.so.6(raise+0x16)[0x7fdbbb03e476]
/lib/x86_64-linux-gnu/libc.so.6(abort+0xd3)[0x7fdbbb0247f3]
/usr/bin/swift-frontend(+0x722811f)[0x55ab7915111f]
/usr/bin/swift-frontend(+0x1fdd0ae)[0x55ab73f060ae]
/usr/bin/swift-frontend(+0x1fe134b)[0x55ab73f0a34b]
/usr/bin/swift-frontend(+0x1fdfabd)[0x55ab73f08abd]
/usr/bin/swift-frontend(+0x1fdf782)[0x55ab73f08782]
/usr/bin/swift-frontend(+0x1fe1ad6)[0x55ab73f0aad6]
/usr/bin/swift-frontend(+0x1fe1969)[0x55ab73f0a969]
/usr/bin/swift-frontend(+0x2009bf2)[0x55ab73f32bf2]
/usr/bin/swift-frontend(+0x200cec4)[0x55ab73f35ec4]
/usr/bin/swift-frontend(+0x1ff1cbf)[0x55ab73f1acbf]
/usr/bin/swift-frontend(+0x1fec2f0)[0x55ab73f152f0]
/usr/bin/swift-frontend(+0x1fea9c9)[0x55ab73f139c9]
/usr/bin/swift-frontend(+0x1fe3462)[0x55ab73f0c462]
/usr/bin/swift-frontend(+0x1518ace)[0x55ab73441ace]
/usr/bin/swift-frontend(+0x15182a3)[0x55ab734412a3]
/usr/bin/swift-frontend(+0x151931c)[0x55ab7344231c]
/usr/bin/swift-frontend(+0x15166f4)[0x55ab7343f6f4]
/usr/bin/swift-frontend(+0x151c5c7)[0x55ab734455c7]
/usr/bin/swift-frontend(+0x15fca8c)[0x55ab73525a8c]
/usr/bin/swift-frontend(+0x151f8df)[0x55ab734488df]
/usr/bin/swift-frontend(+0x151cfdf)[0x55ab73445fdf]
/usr/bin/swift-frontend(+0xe34965)[0x55ab72d5d965]
/usr/bin/swift-frontend(+0xe4a7f5)[0x55ab72d737f5]
/usr/bin/swift-frontend(+0xe382ad)[0x55ab72d612ad]
/usr/bin/swift-frontend(+0xe369db)[0x55ab72d5f9db]
/usr/bin/swift-frontend(+0xcc3315)[0x55ab72bec315]
/lib/x86_64-linux-gnu/libc.so.6(+0x29d90)[0x7fdbbb025d90]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0x80)[0x7fdbbb025e40]
/usr/bin/swift-frontend(+0xcc2375)[0x55ab72beb375]
*** Signal 11: Backtracing from 0x7fdbbb024898... done ***
*** Program crashed: Bad pointer dereference at 0x0000000000000000 ***
Thread 0 "swift-frontend" crashed:
0  0x00007fdbbb024898 <unknown> in libc.so.6
Registers:
rax 0x0000000000000000  0
rdx 0x00007fdbbaefb840  40 b8 ef ba db 7f 00 00 60 c2 ef ba db 7f 00 00  @¸ïºÛ···`ÂïºÛ···
rcx 0x00007fdbbb0929fc  41 89 c5 41 f7 dd 3d 00 f0 ff ff b8 00 00 00 00  A·ÅA÷Ý=·ðÿÿ¸····
rbx 0x0000000000000006  6
rsi 0x0000000000000001  1
rdi 0x0000000000000001  1
rbp 0x00007fdbbb217e90  01 00 00 00 01 00 00 00 40 b8 ef ba db 7f 00 00  ········@¸ïºÛ···
rsp 0x00007ffd594be900  20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   ···············
 r8 0x0000000000000000  0
 r9 0x0000000000000000  0
r10 0x0000000000000008  8
r11 0x0000000000000246  582
r12 0x0000000000000046  70
r13 0x00007ffd594bedb0  00 00 00 00 00 00 00 00 00 66 5f 7e ab 55 00 00  ·········f_~«U··
r14 0x00000000000000d3  211
r15 0x000055ab7ad0d545  2f 68 6f 6d 65 2f 62 75 69 6c 64 2d 75 73 65 72  /home/build-user
rip 0x00007fdbbb024898  f4 83 3d 00 36 1f 00 05 75 14 c7 05 f4 35 1f 00  ô·=·6···u·Ç·ô5··
rflags 0x0000000000010246  ZF PF
cs 0x0033  fs 0x0000  gs 0x0000
Images (23 omitted):
0x00007fdbbaffc000–0x00007fdbbb1b8341 c289da5071a3399de893d2af81d6a30c62646e1e libc.so.6 /usr/lib/x86_64-linux-gnu/libc.so.6
Backtrace took 0.00s

Expected behavior

it worked in 5.9

Environment

Swift version 5.10-dev (LLVM dbfaba0078e9380, Swift 63c8b55)
Target: x86_64-unknown-linux-gnu

Additional information

it also crashes on main

the crash can be mitigated, but not worked around, by making the parameter consuming instead of borrowing

- func f(x:[Int]?)
+ func f(x:consuming [Int]?)
{
}
func g()
{
    let x:[Int]? = nil
    return f(x: consume x)
}

[jckarter]

#71964 addresses the crash, though after addressing the crash I still get an unhelpful diagnostic, so it's not a complete fix:

/Users/jgroff/test2.swift:7:10: error: 'consume' applied to value that the compiler does not support. This is a compiler bug. Please file a bug with a small example of the bug
 5 │ {
 6 │     let x:[Int]? = nil
 7 │     f(x: consume x)
   │          ╰─ error: 'consume' applied to value that the compiler does not support. This is a compiler bug. Please file a bug with a small example of the bug

[nate-chandler]

Fixed by 373cc84