--Debugger:native is broken by nil strings comparison commit

[mratsim]

Test case

echo 1

Compile with --debugger:native: SIGSEGV: Illegal storage access. (Attempt to read from nil?)

Bisect points to this commit: f64f9e5

[cheatfate]

Compiler crash log

nim.nim(113)             nim
nim.nim(77)              handleCmdLine
main.nim(172)            mainCommand
main.nim(78)             commandCompileToC
cgen.nim(1499)           cgenWriteModules
cgen.nim(1429)           writeModule
cgen.nim(1390)           shouldRecompile
ropes.nim(347)           equalsFile
ropes.nim(194)           equalsFile
system.nim(3788)         failedAssertImpl
system.nim(3781)         raiseAssert
system.nim(2843)         sysFatal
Error: unhandled exception:
not (it == nil)  [AssertionError]
FAILURE

[mratsim]

Probably duplicate of #7730