diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,8 @@
+## Version 0.8.0.4 (2020-12-06)
+
+- Fix out of range access in Intro.partialSort.
+- Update QuickCheck dependency bounds.
+
 ## Version 0.8.0.3 (2019-12-02)
 
 - Fix out-of-bounds access in Timsort.
diff --git a/src/Data/Vector/Algorithms/Intro.hs b/src/Data/Vector/Algorithms/Intro.hs
--- a/src/Data/Vector/Algorithms/Intro.hs
+++ b/src/Data/Vector/Algorithms/Intro.hs
@@ -190,7 +190,10 @@
   -> m ()
 partialSortByBounds cmp a k l u
   | l >= u    = return ()
-  | otherwise = go (ilg len) l (l + k) u
+  | otherwise = let k' = min (u-l) k
+                      -- N.B. Clamp k to the length of the range
+                      -- being sorted.
+                in go (ilg len) l (l + k') u
  where
  isort = introsort cmp a
  {-# INLINE [1] isort #-}
diff --git a/vector-algorithms.cabal b/vector-algorithms.cabal
--- a/vector-algorithms.cabal
+++ b/vector-algorithms.cabal
@@ -1,5 +1,5 @@
 name:              vector-algorithms
-version:           0.8.0.3
+version:           0.8.0.4
 license:           BSD3
 license-file:      LICENSE
 author:            Dan Doel
@@ -13,7 +13,7 @@
 description:       Efficient algorithms for sorting vector arrays. At some stage
                    other vector algorithms may be added.
 build-type:        Simple
-cabal-version:     >= 1.9.2
+cabal-version:     >= 1.10
 extra-source-files: CHANGELOG.md
 
 
@@ -54,6 +54,7 @@
 
 library
   hs-source-dirs: src
+  default-language: Haskell2010
 
   build-depends: base >= 4.5 && < 5,
                  vector >= 0.6 && < 0.13,
@@ -105,6 +106,7 @@
 benchmark simple-bench
   hs-source-dirs: bench/simple
   type: exitcode-stdio-1.0
+  default-language: Haskell2010
 
   if !flag(bench)
     buildable: False
@@ -128,6 +130,7 @@
   hs-source-dirs: tests/properties
   type: exitcode-stdio-1.0
   main-is: Tests.hs
+  default-language: Haskell2010
 
   other-modules:
     Optimal
@@ -141,9 +144,10 @@
       base,
       bytestring,
       containers,
-      QuickCheck > 2.9 && < 2.14,
+      QuickCheck > 2.9 && < 2.15,
       vector,
       vector-algorithms
 
   if flag(llvm)
     ghc-options: -fllvm
+