Compiler space regression in 7.0.1 RC 1

There's a compiler space regresion in 7.0.1 RC 1. Seems to be around a factor of 2. Compiling WURFL-0.1

With a cut-down version, note the "<n>M in use":

$ ghc --version
The Glorious Glasgow Haskell Compilation System, version 6.12.3
$ ghc --make WURFL -O -dshow-passes +RTS -t
[...]
<<ghc: 908052456 bytes, 1592 GCs, 7050782/13011048 avg/max bytes residency (15 samples), 31M in use, 0.00 INIT (0.00 elapsed), 1.11 MUT (1.28 elapsed), 0.91 GC (0.86 elapsed) :ghc>>

$ ghc --version
The Glorious Glasgow Haskell Compilation System, version 7.0.0.20100924
$ time ghc --make WURFL -O -dshow-passes +RTS
<<ghc: 973268040 bytes, 1699 GCs, 8225353/20188024 avg/max bytes residency (13 samples), 52M in use, 0.00 INIT (0.00 elapsed), 1.33 MUT (1.41 elapsed), 0.87 GC (0.94 elapsed) :ghc>>

The Result sizes look comparable between the two compilers, so the next step is probably to try with a profiled compiler.

Trac metadata

Trac field	Value
Version	7.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	high
Resolution	Unresolved
Component	Compiler
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