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https://github.com/nim-lang/Nim.git
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3617d2e077
```nim
proc foo =
var x = "1234"
var y = x
when nimvm:
discard
else:
var s = x
doAssert s == "1234"
doAssert y == "1234"
static: foo()
foo()
```
`dfa` chooses the `nimvm` branch, `x` is misread as a last read and
`wasMoved`.
`injectDestructor` is used for codegen and is not used for vmgen. It's
reasonable to choose the codegen path instead of the `nimvm` path so the
code works for codegen. Though the problem is often hidden by
`cursorinference` or `optimizer`.
found in https://github.com/nim-lang/Nim/pull/24831
66 lines
1.1 KiB
Nim
66 lines
1.1 KiB
Nim
discard """
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output: '''
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Deallocating OwnedString
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HelloWorld
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'''
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matrix: "--cursorinference:on; --cursorinference:off"
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target: "c"
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"""
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# bug #23837
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{.
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emit: [
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"""
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#include <stdlib.h>
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#include <string.h>
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char *allocCString() {
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char *result = (char *) malloc(10 + 1);
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strcpy(result, "HelloWorld");
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return result;
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}
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"""
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]
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.}
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proc rawWrapper(): cstring {.importc: "allocCString", cdecl.}
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proc free(p: pointer) {.importc: "free", cdecl.}
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# -------------------------
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type OwnedString = distinct cstring
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proc `=destroy`(s: OwnedString) =
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free(cstring s)
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echo "Deallocating OwnedString"
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func `$`(s: OwnedString): string {.borrow.}
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proc leakyWrapper(): string =
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let ostring = rawWrapper().OwnedString
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$ostring
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# -------------------------
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proc main() =
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# destructor not called - definitely lost: 11 bytes in 1 blocks
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# doesn't leak with --cursorInference:off
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let s = leakyWrapper()
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echo s
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main()
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block:
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proc foo =
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var x = "1234"
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var y = x
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when nimvm:
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discard
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else:
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var s = x
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doAssert s == "1234"
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doAssert y == "1234"
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static: foo()
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foo()
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