A bug in dependency analysis of type declarations in the presence of type families (#5826) has been fixed.

The "Heap exhausted" error message was truncating the reported heap size to 32 bits (#5838). This has now been fixed.

The register clobber list in the ARM runtime now includes extra registers (#5824).

A crash due to a buffer overflow during RTS argument processing (#5851) has been fixed.

A blocked STM computation inside unsafePerformIO or unsafeInterleaveIO would segfault when resuming after an asynchronous exception (#5866). This has now been fixed.

A race condition when creating directories during parallel builds (#5891) has been fixed.

Changed behavior of the --main-is flag so that it forces recompilation of fewer modules (#5878).

The wording of the help text for the -N flag has been improved (#5896).

Fixed command line options passed to clang, when used as the assembler (#5903).

Changed behavior of unrecognized flags (#5921). Any unrecognized argument starting with a '-' now produces an error, instead of being passed to the linker.

A bug in code generation on PowerPC (#5900) resulting in an invalid operand for a shift instruction has been fixed.

Updated LLVM backend to support the new "fence" instruction instead of the llvm.memory.barrier intrinsic (#5814).

ARM support in the RTS linker (#5839) has been implemented.

An RTS crash in threadStackOverflow (#5214) has been fixed.

Generating an occurence without a binding site within a Template Haskell splice now results in a sensible error message, instead of a compiler panic (#5999, #5971).

A bug where an exception generated in a TH splice would escape to the top level (#5976) has been fixed.

When using -fwarn-unsafe, GHC now reports unsafe language extensions.

The non-threaded RTS now avoids wakeups when the system is idle (#5991).

A bug causing a crash with a very small initial stack size (#5993) has been fixed.

A performance bug causing functions to lose the tail-recursive property after optimization (#5920, #5997) has been fixed.

hs_init can now be called with NULL pointers as arguments (#6006).

Fixed bug (#5836) where GHCi would silently accept an import statement for a non-existing module.

Fixed bug (#5904) which caused GHCi to crash when a *-module was loaded twice.

The :edit command in GHCi now causes the current module to be automatically reloaded after exiting from the editor (#5343).

A GHCi bug (#5534) causing compiled modules not to be loaded correctly has been fixed.

A GHCi bug (#5979, #6007) where a failed import would cause successive imports to fail has been fixed.

Fixed bug (#5872) in the default implementation of popCount in Data.Bits.

A potential race condition in Control.Concurrent.Chan (#5870) has been fixed.

An MVar bug which could cause deadlocks (#5943) has been fixed.

Fixed a bug in hGetBufSome (#5843) which was causing Data.ByteString.hGetSome to block on Windows in some situations.

Fixed crash while parsing numeric values in exponential notation (#5688).

hp2ps can now handle backslashes in identifiers correctly (#5800).

A haddock bug (#5989) where modules were being incorrectly inferred safe has been fixed.