ghc-7.4.2 on sparc solaris without threaded rts

my build of ghc-7.4.2 could not link binaries compiled with "-threaded" ("ld: library -lHSrts_thr: not found"). In fact RTS ways does not include "thr" entries as was the case for ghc-7.0.4. Why?

 [("Project name","The Glorious Glasgow Haskell Compilation System")
 ,("GCC extra via C opts"," -fwrapv")
 ,("C compiler command","/opt/csw/bin/gcc")
 ,("C compiler flags"," -fno-stack-protector ")
 ,("ar command","/usr/ccs/bin/ar")
 ,("ar flags","clqs")
 ,("ar supports at file","@ArSupportsAtFile@")
 ,("touch command","touch")
 ,("dllwrap command","/bin/false")
 ,("windres command","/bin/false")
 ,("perl command","/usr/bin/perl")
 ,("target os","OSSolaris2")
 ,("target arch","ArchSPARC")
 ,("target word size","4")
 ,("target has GNU nonexec stack","True")
 ,("target has subsections via symbols","False")
 ,("Project version","7.4.2")
 ,("Booter version","7.0.4")
 ,("Stage","2")
 ,("Build platform","sparc-sun-solaris2")
 ,("Host platform","sparc-sun-solaris2")
 ,("Target platform","sparc-sun-solaris2")
 ,("Have interpreter","YES")
 ,("Object splitting supported","NO")
 ,("Have native code generator","NO")
 ,("Support SMP","NO")
 ,("Unregisterised","YES")
 ,("Tables next to code","YES")
 ,("RTS ways","l debug    ")
 ,("Leading underscore","NO")
 ,("Debug on","False")
 ,("LibDir","/home/pub-bkb/ghc/ghc-7.4.2/lib/ghc-7.4.2")
 ,("Global Package DB","/home/pub-bkb/ghc/ghc-7.4.2/lib/ghc-7.4.2/package.conf.d")
 ,("Gcc Linker flags","[]")
 ,("Ld Linker flags","[]")
 ]

I'm on solaris 10 "SunOS 5.10 Generic_147440-21 sun4u sparc SUNW,Sun-Fire-280R", gcc-4.6.3, and ld: Software Generation Utilities - Solaris Link Editors: 5.10-1.1510

Trac metadata

Trac field	Value
Version	7.4.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
Test case
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