[SR-1177] Getting value from Dictionary crashes when built with -Onone

[swift-ci]

Previous ID	SR-1177
Radar	None
Original Reporter	wczekalski (JIRA User)
Type	Bug
Status	Resolved
Resolution	Invalid

Attachment: Download

Environment

Apple Swift version 3.0-dev (LLVM b361b0fc05, Clang 11493b0f62, Swift 24a0c3d) (03/01/2016 development snapshot)

Additional Detail from JIRA

Votes	0
Component/s	Standard Library
Labels	Bug, NotOptimizedOnly
Assignee	None
Priority	Medium

md5: 9ab249de5a5e7ae6894b3afdf799732d

Issue Description:

When I get a value from a Dictionary it crashes. The crash happens in various places in the call stack of the subscript getter. It happens only if the build is compiled without Swift compiler optimizations on biggish data sets (tested with 10000 elements). It is probably generics related. I attached a sample program.

[belkadan]

Starting on the standard library, cc @gribozavr

[gribozavr]

You're running out of stack space, crashing on the call instruction. There are more than 8 thousand frames in the stack trace.

(lldb) r
There is a running process, kill it and restart?: [Y/n] y
Process 84844 exited with status = 9 (0x00000009)
Process 84851 launched: './main' (x86_64)
Process 84851 stopped
* thread #​1: tid = 0x38a04b, 0x00000001000aada3 libswiftCore.dylib`Swift._VariantSetStorage.isUniquelyReferenced () -> Swift.Bool + 35, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=2, address=0x7fff5f3ffff8)
    frame #​0: 0x00000001000aada3 libswiftCore.dylib`Swift._VariantSetStorage.isUniquelyReferenced () -> Swift.Bool + 35
libswiftCore.dylib`Swift._VariantSetStorage.isUniquelyReferenced () -> Swift.Bool:
->  0x1000aada3 <+35>: callq  0x10020b46c               ; symbol stub for: object_getClass