2 files changed, 16 insertions, 2 deletions

diff --git a/hmatrix.cabal b/hmatrix.cabal
index aeef52c..cae34a2 100644
--- a/hmatrix.cabal
+++ b/hmatrix.cabal
@@ -33,6 +33,10 @@ flag no-workaround
     description:    Expose the NaN problem
     default: False
 
+flag expose-bug
+    description:    Expose the NaN problem with debug information
+    default: False
+
 library
     if flag(splitBase)
       build-depends:    base >= 3, array, QuickCheck, HUnit, storable-complex
@@ -107,9 +111,13 @@ library
     if flag(unsafe)
         cpp-options: -DUNSAFE
 
-    if arch(i386) && !flag(no-workaround) && !flag(mkl)
+    if arch(i386) && !flag(no-workaround) && !flag(expose-bug) && !flag(mkl)
         cpp-options: -DWORKAROUND
 
+    if flag(expose-bug)
+        cpp-options: -DEXPOSEBUG
+
+
     if flag(mkl)
       if arch(x86_64)
         extra-libraries:   gsl mkl_lapack mkl_intel_lp64 mkl_sequential mkl_core
diff --git a/lib/Numeric/LinearAlgebra/Algorithms.hs b/lib/Numeric/LinearAlgebra/Algorithms.hs
index 2c5f44c..00a0ab0 100644
--- a/lib/Numeric/LinearAlgebra/Algorithms.hs
+++ b/lib/Numeric/LinearAlgebra/Algorithms.hs
@@ -143,8 +143,12 @@ instance Field (Complex Double) where
 #if defined(WORKAROUND)
     multiply = mulCW
 #else
+#if defined(EXPOSEBUG)
+    multiply = multiplyC
+#else
     multiply = multiplyC3
 #endif
+#endif
 
 -- | Eigenvalues and Eigenvectors of a complex hermitian or real symmetric matrix using lapack's dsyev or zheev.
 --
@@ -664,7 +668,9 @@ cmultiply f st a b
       = unsafePerformIO $ do
         s <- createMatrix RowMajor (rows a) (cols b)
         app3 f mat a mat b mat s st
-        if toLists s== toLists s then return s else error $ "BRUTAL " ++ (show (toLists s))
+        if toLists s== toLists s
+            then return s
+            else error $ "NaN FOUND!! " ++ (show (toLists s))
         -- return s
 --    | otherwise = error $ st ++ " (matrix product) of nonconformant matrices"