Running dos2unix on mergesort.f90 and adding declspec export for shared windows build.

radixalgorithm/mergesort.f90

-    subroutine merge_sort(n, a, indices)
-! This routine takes an input array 'a' of dimension (n)
-! and an input array 'indices' of dimension (n)
-! and conducts a merge sort on array 'a' while saving the original order
-! to array 'indices'
-
-! The first pass sorts each pair of consecutive elements [a(i) vs. a(i+1)].
-! The second pass sorts adjacent sequences of length 2 [a(i), a(i+1) vs. a(i+2), a(i+3)]; the sequences are already ordered, due to step 1.
-! The third pass sorts adjacent sequences of length 4 [a(i),...,a(i+3) vs. a(i+4),...,a(i+7)]; the sequences are already ordered, from step 2.
-! This continues for L1 passes, where 2**(L1-1) < n < 2**L1.  Note that n does not need to be a power of 2.
-
-    implicit none
-    integer :: i, imax, i0, j, jmax, k, L, L1, m, n
-    real, intent(inout) :: a(n)
-    integer, intent(out) :: indices(n)
-    real, allocatable :: b(:)
-    allocate (b(n))
-    L1 = 1
-    m  = 1
-    do while (m < n)    ! Determine L1 so that 2**(L1-1) < n < 2**L1
-      m = m + m
-      L1 = L1 + 1
-    end do
-    L1 = L1 - 1
-    m = 1
-    do L=1, L1
-      k=1
-      do i0=1, n-m+1, m+m
-        i=i0
-        j=i+m
-        imax=j
-        jmax=j+m
-        if(imax > n) imax = n + 1
-        if(jmax > n) jmax = n + 1
-        do while(i < imax  .and.  j < jmax)
-          if(a(i) < a(j)) then
-            b(k) = a(i)
-            indices(k) = i
-            i = i + 1
-          else
-            b(k) = a(j)
-            indices(k) = j
-            j = j + 1
-          end if
-          k = k + 1
-        end do
-        do while(i < imax)
-          b(k) = a(i)
-          indices(k) = i
-          i = i + 1
-          k = k + 1
-        end do
-        do while(j < jmax)
-          b(k) = a(j)
-          indices(k) = j
-          j = j + 1
-          k = k + 1
-        end do
-      end do
-      m = m + m
-      a = b
-    end do
-    if(allocated(b)) deallocate(b)
-    return
-    end subroutine merge_sort
-
+    subroutine merge_sort(n, a, indices)
+! This routine takes an input array 'a' of dimension (n)
+! and an input array 'indices' of dimension (n)
+! and conducts a merge sort on array 'a' while saving the original order
+! to array 'indices'
+
+! The first pass sorts each pair of consecutive elements [a(i) vs. a(i+1)].
+! The second pass sorts adjacent sequences of length 2 [a(i), a(i+1) vs. a(i+2), a(i+3)]; the sequences are already ordered, due to step 1.
+! The third pass sorts adjacent sequences of length 4 [a(i),...,a(i+3) vs. a(i+4),...,a(i+7)]; the sequences are already ordered, from step 2.
+! This continues for L1 passes, where 2**(L1-1) < n < 2**L1.  Note that n does not need to be a power of 2.
+
+    implicit none
+    !DEC$ ATTRIBUTES DLLEXPORT::merge_sort
+    integer :: i, imax, i0, j, jmax, k, L, L1, m, n
+    real, intent(inout) :: a(n)
+    integer, intent(out) :: indices(n)
+    real, allocatable :: b(:)
+    allocate (b(n))
+    L1 = 1
+    m  = 1
+    do while (m < n)    ! Determine L1 so that 2**(L1-1) < n < 2**L1
+      m = m + m
+      L1 = L1 + 1
+    end do
+    L1 = L1 - 1
+    m = 1
+    do L=1, L1
+      k=1
+      do i0=1, n-m+1, m+m
+        i=i0
+        j=i+m
+        imax=j
+        jmax=j+m
+        if(imax > n) imax = n + 1
+        if(jmax > n) jmax = n + 1
+        do while(i < imax  .and.  j < jmax)
+          if(a(i) < a(j)) then
+            b(k) = a(i)
+            indices(k) = i
+            i = i + 1
+          else
+            b(k) = a(j)
+            indices(k) = j
+            j = j + 1
+          end if
+          k = k + 1
+        end do
+        do while(i < imax)
+          b(k) = a(i)
+          indices(k) = i
+          i = i + 1
+          k = k + 1
+        end do
+        do while(j < jmax)
+          b(k) = a(j)
+          indices(k) = j
+          j = j + 1
+          k = k + 1
+        end do
+      end do
+      m = m + m
+      a = b
+    end do
+    if(allocated(b)) deallocate(b)
+    return
+    end subroutine merge_sort
+