GCC does not provide "cc" on guix.  Hence, look for "gcc" instead.

diff --git a/utils/hsc2hs/Common.hs b/utils/hsc2hs/Common.hs
index 50471b1..c8bd297 100644
--- a/utils/hsc2hs/Common.hs
+++ b/utils/hsc2hs/Common.hs
@@ -20,7 +20,7 @@ die :: String -> IO a
 die s = hPutStr stderr s >> exitWith (ExitFailure 1)
 
 default_compiler :: String
-default_compiler = "cc"
+default_compiler = "gcc"
 
 ------------------------------------------------------------------------
 -- Write the output files.