Is "cml_cont" of CmmCall used in practice?

Ömer Sinan Ağacan omeragacan at
Sun Mar 18 07:32:25 UTC 2018

Hi Shao,

Perhaps not in the Cmm output generated for your programs, but it's definitely
used in the code generator. See e.g. `lowerSafeForeignCall` and `blockCode`
which set the field with `Just`. The former seems to be related with foreign
calls so perhaps try compiling a FFI package. `CmmLayoutStack` uses that field
for code generation (I don't understand the details yet).


2018-03-18 8:38 GMT+03:00 Shao, Cheng <cheng.shao at>:
> Hi all,
> Is the "cml_cont" field of the CmmCall variant is really used in practice? I
> traversed the output of raw Cmm produced by ghc compiling the whole base
> package, but the value of cml_cont is always Nothing.
> Regards,
> Shao Cheng
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