Possible bug in strictness analyzer when where clause declared NOINLINE

I've encountered the following error message using a relatively straight forward library that wraps postgresql-simple in certain edge cases:

*** Exception: Oops!  Entered absent arg a_sYDl{v} [lid] bytestring-0.10.4.0:Data.ByteString.Internal.ByteString{tc r5T}

This happens on an invocation of a function, dbSelect under certain compilation conditions:

dbSelect :: (Model a) => Connection -> DBSelect a -> IO [a]
{-# INLINE #-}
dbSelect conn dbs = map lookupRow <$> query_ conn q
  where {-# NOINLINE #-}
    q = renderDBSelect dbs

A DBSelect is just a data-structure with different Query (wrapper around strict bytestring) fields for clauses in a SQL select query. renderDBSelect generates a single Query value from the DBSelect (by way of contructing a Blaze.Builder as an intermediate step).

When compiled with no optimizations, this works fine, no issues. With -O1, I get the error above. The errors goes away, if I compile with -fno-strictness or remove the NOINLINE *or* INLINE pragmas.

We've worked around this for now in the library by removgin the NOINLINE pragmas, but tracking this down it seems like the strictness analyzer might be falsly assuming q is never actually evaluated. For reference, this is a commit that still exhibits the bug: https://github.com/alevy/postgresql-orm/tree/93075d56ae5ffeb8f80ecc8c01436713c2656a6b

I've also attached a small test application that excercises the bug. Because of how the library sets up a scratch database, the test application requires postgres and pg_ctl to be available in the path.

Trac metadata

Trac field	Value
Version	7.8.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
Test case
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Operating system	Unknown/Multiple
Architecture	Unknown/Multiple