In absence of recursive imports, hs-boot files not checked for consistency

Example:

B.hs-boot

module B where
b :: Bool

A.hs

module A where
import {-# SOURCE #-} B
a = b

B.hs

module B where

Main.hs

import A
main = print a

Compilation:

ghc -c B.hs-boot
ghc -c A.hs
ghc -c B.hs
ghc -c Main.hs
ghc -o main A.o B.o Main.o

Error:

A.o:(.text+0x79): undefined reference to `B_b_closure'
A.o: In function `A_a_srt':
(.data+0x0): undefined reference to `B_b_closure'
collect2: error: ld returned 1 exit status

The culprit seems to be this code:

        -- OK, so we're in one-shot mode.
        -- In that case, we're read all the direct imports by now,
        -- so eps_is_boot will record if any of our imports mention us by
        -- way of hi-boot file
        { eps <- getEps
        ; case lookupUFM (eps_is_boot eps) (moduleName mod) of {
            Nothing -> return emptyModDetails ; -- The typical case

            Just (_, False) -> failWithTc moduleLoop ;
                -- Someone below us imported us!
                -- This is a loop with no hi-boot in the way

            Just (_mod, True) ->        -- There's a hi-boot interface below us

but I am not 100% sure what the correct new logic is yet.