Make valgrind testing part of travis ci.

.travis.yml

@@ -9,7 +9,7 @@ matrix:
       addons:
         apt:
           sources: ['ubuntu-toolchain-r-test']
-          packages: ['g++-multilib']
+          packages: ['g++-multilib', 'valgrind']
       env:
         - COMPILER=g++
         - COMP=gcc
@@ -19,7 +19,7 @@ matrix:
       addons:
         apt:
           sources: ['ubuntu-toolchain-r-test']
-          packages: ['clang', 'g++-multilib']
+          packages: ['clang', 'g++-multilib', 'valgrind']
       env:
         - COMPILER=clang++
         - COMP=clang
@@ -49,3 +49,5 @@ script:
   - echo "Checking for same bench numbers..."
   - diff bench1 bench2 > result
   - test ! -s result
+  # if valgrind is available check the build is without error, reduce depth to speedup testing, but not too shallow to catch more cases.
+  - if [ -x "$(command -v valgrind )" ] ; then make clean && make ARCH=x86-64 debug=yes build && valgrind --error-exitcode=42 ./stockfish bench 128 1 10 default depth 1>/dev/null ; fi