Merge branch 'v2.3' into v2.4

.travis.yml

@@ -112,6 +112,9 @@ install:
 # install some package - these are fast, we install them anyway
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo apt-get install -y libmatheval-dev libfftw3-dev gsl-bin libgsl0-dev  libboost-serialization-dev ; fi
   - if test "$PLUMED_CXX" ; then ./.travis/install.xdrfile ; fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then
+      ./.travis/install.ccache v3.4.2 ;
+    fi
 # cppcheck:
 # I use 1.71 since 1.72 seems to report a lot of false positive
   - if test "$CPPCHECK" == yes ; then  ./.travis/install.cppcheck $CPPCHECK_VERSION ; fi

.travis/install.ccache

+#! /bin/bash
+
+set -e
+set -x
+
+cd "$(mktemp -dt plumed.XXXXXX)"
+
+git clone https://github.com/ccache/ccache.git
+
+cd ccache
+
+if [ -n "$1" ] ; then
+  echo "installing ccache $version"
+  version=$1
+else
+  echo "installing latest ccache"
+  version=$(git tag | tail -n 1)
+fi
+
+git checkout $version
+
+./autogen.sh
+./configure --prefix="$HOME/opt"
+make -j 4
+
+# full install does not work as it required asciidoc installed:
+# make install
+
+mkdir -p "$HOME/opt/bin"
+cp ccache $HOME/opt/bin/

CHANGES/v2.3.md

@@ -239,4 +239,5 @@ For developers:
 - `plumed patch -e` now accepts a name closely matching the patch name (e.g. `plumed patch -e gromacs2016.5` will try to patch
   even if the stored patch is for `gromacs-2016.4`). This simplifies managing Portfiles. Nothing changes when picking the patch
   from the interactive menu.
+- Install newer ccache on travis-ci, build faster.