From 5f7e756570e0158f694747d975de0bd587cd6f89 Mon Sep 17 00:00:00 2001
From: Manuel <manuel@binna.de>
Date: Wed, 8 Feb 2017 08:23:36 +0100
Subject: [PATCH 01/25] Ignore out-of-source build directory

---
 .gitignore | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.gitignore b/.gitignore
index 0cc7e4b52..562b07afa 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+build/
 CMakeCache.txt
 CMakeFiles
 CMakeScripts

From 4ed7e8234f4019049c2c0eb09ef18a6e8c34b0c3 Mon Sep 17 00:00:00 2001
From: Manuel <manuel@binna.de>
Date: Wed, 8 Feb 2017 08:24:05 +0100
Subject: [PATCH 02/25] Add Travis CI config file

This config file causes Travis CI to build this project with a matrix
build job. More information:

* https://docs.travis-ci.com/user/languages/cpp
* https://genbattle.bitbucket.io/blog/2016/01/17/c++-travis-ci/?
---
 .travis.yml | 9 +++++++++
 1 file changed, 9 insertions(+)
 create mode 100644 .travis.yml

diff --git a/.travis.yml b/.travis.yml
new file mode 100644
index 000000000..289e1f3eb
--- /dev/null
+++ b/.travis.yml
@@ -0,0 +1,9 @@
+language: cpp
+compiler:
+    - clang
+    - gcc
+script:
+    - mkdir build
+    - cd build
+    - cmake ..
+    - cmake --build .

From a093c2e1b40e1e98ff696f67f057526cff89a4dd Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 21:18:38 +0100
Subject: [PATCH 03/25] Add apt package 'cmake'

---
 .travis.yml | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/.travis.yml b/.travis.yml
index 289e1f3eb..282b7d220 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,6 +2,10 @@ language: cpp
 compiler:
     - clang
     - gcc
+addons:
+    apt:
+        packages:
+            - cmake
 script:
     - mkdir build
     - cd build

From d4d5883f0fa6e35041c6319f0c66b41b51af51b8 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 21:21:56 +0100
Subject: [PATCH 04/25] Explicitly install package 'cmake-3.7'

---
 .travis.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.travis.yml b/.travis.yml
index 282b7d220..f920d71cc 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,7 +5,7 @@ compiler:
 addons:
     apt:
         packages:
-            - cmake
+            - cmake-3.7
 script:
     - mkdir build
     - cd build

From 713b81cf36eb809b8d17ccc316646f40f50386c0 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 21:26:03 +0100
Subject: [PATCH 05/25] Add apt toolchain

---
 .travis.yml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/.travis.yml b/.travis.yml
index f920d71cc..1597b6aca 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,6 +4,8 @@ compiler:
     - gcc
 addons:
     apt:
+        sources:
+            - ubuntu-toolchain-r-test
         packages:
             - cmake-3.7
 script:

From bcfda93315c803e666dd65ac38f262c8e6138d26 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 21:29:29 +0100
Subject: [PATCH 06/25] Use package 'cmake' without version

---
 .travis.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.travis.yml b/.travis.yml
index 1597b6aca..92efb1ea6 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,7 +7,7 @@ addons:
         sources:
             - ubuntu-toolchain-r-test
         packages:
-            - cmake-3.7
+            - cmake
 script:
     - mkdir build
     - cd build

From 454513deb9ab2f0d0fb73ee6312eac182b8a45a9 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 21:43:10 +0100
Subject: [PATCH 07/25] Install a recent version of CMake manually

---
 .travis.yml | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 92efb1ea6..6f57f1416 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,8 +6,12 @@ addons:
     apt:
         sources:
             - ubuntu-toolchain-r-test
-        packages:
-            - cmake
+install:
+    # Install a recent version of CMake (source: https://github.com/boostorg/hana/blob/master/.travis.yml)
+    - |
+        CMAKE_URL="https://cmake.org/files/v3.7/cmake-3.7.2-Linux-x86_64.sh"
+        mkdir cmake && travis_retry wget --no-check-certificate --quiet -O - ${CMAKE_URL} | tar --strip-components=1 -xz -C cmake
+        export PATH=${DEPS_DIR}/cmake/bin:${PATH}
 script:
     - mkdir build
     - cd build

From 5032256cdeaf29186aaae7a51747169b207e97cc Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 21:47:29 +0100
Subject: [PATCH 08/25] Add and cd into directory

---
 .travis.yml | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/.travis.yml b/.travis.yml
index 6f57f1416..97242fecb 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,6 +7,9 @@ addons:
         sources:
             - ubuntu-toolchain-r-test
 install:
+    - DEPS_DIR="${TRAVIS_BUILD_DIR}/deps"
+    - mkdir -p "${DEPS_DIR}" && cd "${DEPS_DIR}"
+
     # Install a recent version of CMake (source: https://github.com/boostorg/hana/blob/master/.travis.yml)
     - |
         CMAKE_URL="https://cmake.org/files/v3.7/cmake-3.7.2-Linux-x86_64.sh"

From c99b61867861618c2fbb72c5fd07079e1d146cce Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 21:51:55 +0100
Subject: [PATCH 09/25] Fix CMake URL

---
 .travis.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.travis.yml b/.travis.yml
index 97242fecb..40cebd8c5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,7 +12,7 @@ install:
 
     # Install a recent version of CMake (source: https://github.com/boostorg/hana/blob/master/.travis.yml)
     - |
-        CMAKE_URL="https://cmake.org/files/v3.7/cmake-3.7.2-Linux-x86_64.sh"
+        CMAKE_URL="https://cmake.org/files/v3.7/cmake-3.7.2-Linux-x86_64.tar.gz"
         mkdir cmake && travis_retry wget --no-check-certificate --quiet -O - ${CMAKE_URL} | tar --strip-components=1 -xz -C cmake
         export PATH=${DEPS_DIR}/cmake/bin:${PATH}
 script:

From 987752eb58927dc31678cb29ec21f8cd92ad03d0 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 21:54:47 +0100
Subject: [PATCH 10/25] Change directory before running script

---
 .travis.yml | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/.travis.yml b/.travis.yml
index 40cebd8c5..c3ec22477 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,3 +1,5 @@
+# Source: https://github.com/boostorg/hana/blob/master/.travis.yml
+
 language: cpp
 compiler:
     - clang
@@ -10,11 +12,13 @@ install:
     - DEPS_DIR="${TRAVIS_BUILD_DIR}/deps"
     - mkdir -p "${DEPS_DIR}" && cd "${DEPS_DIR}"
 
-    # Install a recent version of CMake (source: https://github.com/boostorg/hana/blob/master/.travis.yml)
+    # Install a recent version of CMake
     - |
         CMAKE_URL="https://cmake.org/files/v3.7/cmake-3.7.2-Linux-x86_64.tar.gz"
         mkdir cmake && travis_retry wget --no-check-certificate --quiet -O - ${CMAKE_URL} | tar --strip-components=1 -xz -C cmake
         export PATH=${DEPS_DIR}/cmake/bin:${PATH}
+before_script:
+    - cd "${TRAVIS_BUILD_DIR}"
 script:
     - mkdir build
     - cd build

From c343091824a5e33e0b34f484f80af1154dcbc270 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 21:57:32 +0100
Subject: [PATCH 11/25] Install package 'protobuf'

---
 .travis.yml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/.travis.yml b/.travis.yml
index c3ec22477..15d753d38 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,6 +8,8 @@ addons:
     apt:
         sources:
             - ubuntu-toolchain-r-test
+        packages:
+            - protobuf
 install:
     - DEPS_DIR="${TRAVIS_BUILD_DIR}/deps"
     - mkdir -p "${DEPS_DIR}" && cd "${DEPS_DIR}"

From 885fa536def260280456b663108673cd6b067b03 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 22:14:37 +0100
Subject: [PATCH 12/25] Install recent version of protobuf compiler

---
 .travis.yml | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/.travis.yml b/.travis.yml
index 15d753d38..66153ff03 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -19,6 +19,13 @@ install:
         CMAKE_URL="https://cmake.org/files/v3.7/cmake-3.7.2-Linux-x86_64.tar.gz"
         mkdir cmake && travis_retry wget --no-check-certificate --quiet -O - ${CMAKE_URL} | tar --strip-components=1 -xz -C cmake
         export PATH=${DEPS_DIR}/cmake/bin:${PATH}
+
+    # Install a recent version of the Protobuf Compiler
+     - |
+        mkdir -p protoc-3.2.0-linux-x86_64 && cd protoc-3.2.0-linux-x86_64
+        wget https://github.com/google/protobuf/releases/download/v3.2.0/protoc-3.2.0-linux-x86_64.zip
+        unzip protoc-3.2.0-linux-x86_64.zip
+        export PATH=${DEPS_DIR}/protoc-3.2.0-linux-x86_64/bin:${PATH}
 before_script:
     - cd "${TRAVIS_BUILD_DIR}"
 script:

From c06f42a3cc45d899641067eb56acf97b4ea589ca Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 22:17:55 +0100
Subject: [PATCH 13/25] Fix .travis.yml format

---
 .travis.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.travis.yml b/.travis.yml
index 66153ff03..b1b93470e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -21,7 +21,7 @@ install:
         export PATH=${DEPS_DIR}/cmake/bin:${PATH}
 
     # Install a recent version of the Protobuf Compiler
-     - |
+    - |
         mkdir -p protoc-3.2.0-linux-x86_64 && cd protoc-3.2.0-linux-x86_64
         wget https://github.com/google/protobuf/releases/download/v3.2.0/protoc-3.2.0-linux-x86_64.zip
         unzip protoc-3.2.0-linux-x86_64.zip

From 9c9ab5166bbdfac5e45475612fc4be75057fdd30 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 22:19:07 +0100
Subject: [PATCH 14/25] Remove apt package 'protobuf'

---
 .travis.yml | 2 --
 1 file changed, 2 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index b1b93470e..0ddd8da41 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,8 +8,6 @@ addons:
     apt:
         sources:
             - ubuntu-toolchain-r-test
-        packages:
-            - protobuf
 install:
     - DEPS_DIR="${TRAVIS_BUILD_DIR}/deps"
     - mkdir -p "${DEPS_DIR}" && cd "${DEPS_DIR}"

From 6d502f1172a4af1ef6facdac4d73ae62eae245ac Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 22:36:10 +0100
Subject: [PATCH 15/25] Install recent version of protobuf

---
 .travis.yml | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 0ddd8da41..39ed9bac0 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -15,15 +15,19 @@ install:
     # Install a recent version of CMake
     - |
         CMAKE_URL="https://cmake.org/files/v3.7/cmake-3.7.2-Linux-x86_64.tar.gz"
-        mkdir cmake && travis_retry wget --no-check-certificate --quiet -O - ${CMAKE_URL} | tar --strip-components=1 -xz -C cmake
+        mkdir cmake
+        travis_retry wget --no-check-certificate --quiet -O - ${CMAKE_URL} | tar --strip-components=1 -xz -C cmake
         export PATH=${DEPS_DIR}/cmake/bin:${PATH}
 
-    # Install a recent version of the Protobuf Compiler
+    # Install a recent version of the Protobuf
     - |
-        mkdir -p protoc-3.2.0-linux-x86_64 && cd protoc-3.2.0-linux-x86_64
-        wget https://github.com/google/protobuf/releases/download/v3.2.0/protoc-3.2.0-linux-x86_64.zip
-        unzip protoc-3.2.0-linux-x86_64.zip
-        export PATH=${DEPS_DIR}/protoc-3.2.0-linux-x86_64/bin:${PATH}
+        PROTOBUF_URL="https://github.com/google/protobuf/releases/download/v3.2.0/protobuf-cpp-3.2.0.tar.gz"
+        mkdir protobuf
+        travis_retry wget --no-check-certificate --quiet -O - ${PROTOBUF_URL} | tar --strip-components=1 -xz -C protobuf
+        cd protobuf
+        ./configure --prefix=/usr
+        make
+        make install
 before_script:
     - cd "${TRAVIS_BUILD_DIR}"
 script:

From 619f0cabcd4b770d24e4fa91429319869e4665d2 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 22:47:05 +0100
Subject: [PATCH 16/25] Use sudo and cache some directories

---
 .travis.yml | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/.travis.yml b/.travis.yml
index 39ed9bac0..8e48c3542 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,7 @@
 # Source: https://github.com/boostorg/hana/blob/master/.travis.yml
 
 language: cpp
+sudo: true
 compiler:
     - clang
     - gcc
@@ -8,6 +9,10 @@ addons:
     apt:
         sources:
             - ubuntu-toolchain-r-test
+cache:
+    directories:
+        - ${TRAVIS_BUILD_DIR}/deps/cmake
+        - ${TRAVIS_BUILD_DIR}/deps/protobuf
 install:
     - DEPS_DIR="${TRAVIS_BUILD_DIR}/deps"
     - mkdir -p "${DEPS_DIR}" && cd "${DEPS_DIR}"

From 5e1bc096a980b10687ebb4ca9277549e5b59667c Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 22:56:09 +0100
Subject: [PATCH 17/25] Use dist Trusty

---
 .travis.yml | 33 ++++-----------------------------
 1 file changed, 4 insertions(+), 29 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 8e48c3542..72ce3de91 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,7 +1,5 @@
-# Source: https://github.com/boostorg/hana/blob/master/.travis.yml
-
+dist: trusty
 language: cpp
-sudo: true
 compiler:
     - clang
     - gcc
@@ -9,32 +7,9 @@ addons:
     apt:
         sources:
             - ubuntu-toolchain-r-test
-cache:
-    directories:
-        - ${TRAVIS_BUILD_DIR}/deps/cmake
-        - ${TRAVIS_BUILD_DIR}/deps/protobuf
-install:
-    - DEPS_DIR="${TRAVIS_BUILD_DIR}/deps"
-    - mkdir -p "${DEPS_DIR}" && cd "${DEPS_DIR}"
-
-    # Install a recent version of CMake
-    - |
-        CMAKE_URL="https://cmake.org/files/v3.7/cmake-3.7.2-Linux-x86_64.tar.gz"
-        mkdir cmake
-        travis_retry wget --no-check-certificate --quiet -O - ${CMAKE_URL} | tar --strip-components=1 -xz -C cmake
-        export PATH=${DEPS_DIR}/cmake/bin:${PATH}
-
-    # Install a recent version of the Protobuf
-    - |
-        PROTOBUF_URL="https://github.com/google/protobuf/releases/download/v3.2.0/protobuf-cpp-3.2.0.tar.gz"
-        mkdir protobuf
-        travis_retry wget --no-check-certificate --quiet -O - ${PROTOBUF_URL} | tar --strip-components=1 -xz -C protobuf
-        cd protobuf
-        ./configure --prefix=/usr
-        make
-        make install
-before_script:
-    - cd "${TRAVIS_BUILD_DIR}"
+        package:
+            - cmake
+            - protobuf
 script:
     - mkdir build
     - cd build

From 05170816e1fe4898b267f3c482d633623a151127 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 22:59:18 +0100
Subject: [PATCH 18/25] Run apt-get update

---
 .travis.yml | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 72ce3de91..9222b5cea 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,13 +3,9 @@ language: cpp
 compiler:
     - clang
     - gcc
-addons:
-    apt:
-        sources:
-            - ubuntu-toolchain-r-test
-        package:
-            - cmake
-            - protobuf
+before_install:
+    - sudo apt-get -qq update
+    - sudo apt-get install -y cmake protobuf
 script:
     - mkdir build
     - cd build

From 65cad82592f51513759de701ea3517da00acc36e Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Wed, 8 Feb 2017 23:03:53 +0100
Subject: [PATCH 19/25] Install protobuf-c-compiler

---
 .travis.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.travis.yml b/.travis.yml
index 9222b5cea..047dd06df 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,7 +5,7 @@ compiler:
     - gcc
 before_install:
     - sudo apt-get -qq update
-    - sudo apt-get install -y cmake protobuf
+    - sudo apt-get install -y cmake protobuf-c-compiler
 script:
     - mkdir build
     - cd build

From a4becf94c5739b78fb47d6bb4f95117c60445b45 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Thu, 9 Feb 2017 06:41:58 +0100
Subject: [PATCH 20/25] Revert "Install protobuf-c-compiler"

This reverts commit 65cad82592f51513759de701ea3517da00acc36e.
---
 .travis.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.travis.yml b/.travis.yml
index 047dd06df..9222b5cea 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,7 +5,7 @@ compiler:
     - gcc
 before_install:
     - sudo apt-get -qq update
-    - sudo apt-get install -y cmake protobuf-c-compiler
+    - sudo apt-get install -y cmake protobuf
 script:
     - mkdir build
     - cd build

From 05e2ab79660a5cd72f736ad6e7d4bd713bb1b817 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Thu, 9 Feb 2017 06:42:14 +0100
Subject: [PATCH 21/25] Revert "Run apt-get update"

This reverts commit 05170816e1fe4898b267f3c482d633623a151127.
---
 .travis.yml | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 9222b5cea..72ce3de91 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,9 +3,13 @@ language: cpp
 compiler:
     - clang
     - gcc
-before_install:
-    - sudo apt-get -qq update
-    - sudo apt-get install -y cmake protobuf
+addons:
+    apt:
+        sources:
+            - ubuntu-toolchain-r-test
+        package:
+            - cmake
+            - protobuf
 script:
     - mkdir build
     - cd build

From fbd2555c2d84befc54a72a28c01ce7ae35b8b8aa Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Thu, 9 Feb 2017 06:42:23 +0100
Subject: [PATCH 22/25] Revert "Use dist Trusty"

This reverts commit 5e1bc096a980b10687ebb4ca9277549e5b59667c.
---
 .travis.yml | 33 +++++++++++++++++++++++++++++----
 1 file changed, 29 insertions(+), 4 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 72ce3de91..8e48c3542 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,5 +1,7 @@
-dist: trusty
+# Source: https://github.com/boostorg/hana/blob/master/.travis.yml
+
 language: cpp
+sudo: true
 compiler:
     - clang
     - gcc
@@ -7,9 +9,32 @@ addons:
     apt:
         sources:
             - ubuntu-toolchain-r-test
-        package:
-            - cmake
-            - protobuf
+cache:
+    directories:
+        - ${TRAVIS_BUILD_DIR}/deps/cmake
+        - ${TRAVIS_BUILD_DIR}/deps/protobuf
+install:
+    - DEPS_DIR="${TRAVIS_BUILD_DIR}/deps"
+    - mkdir -p "${DEPS_DIR}" && cd "${DEPS_DIR}"
+
+    # Install a recent version of CMake
+    - |
+        CMAKE_URL="https://cmake.org/files/v3.7/cmake-3.7.2-Linux-x86_64.tar.gz"
+        mkdir cmake
+        travis_retry wget --no-check-certificate --quiet -O - ${CMAKE_URL} | tar --strip-components=1 -xz -C cmake
+        export PATH=${DEPS_DIR}/cmake/bin:${PATH}
+
+    # Install a recent version of the Protobuf
+    - |
+        PROTOBUF_URL="https://github.com/google/protobuf/releases/download/v3.2.0/protobuf-cpp-3.2.0.tar.gz"
+        mkdir protobuf
+        travis_retry wget --no-check-certificate --quiet -O - ${PROTOBUF_URL} | tar --strip-components=1 -xz -C protobuf
+        cd protobuf
+        ./configure --prefix=/usr
+        make
+        make install
+before_script:
+    - cd "${TRAVIS_BUILD_DIR}"
 script:
     - mkdir build
     - cd build

From 775d4544cbc5ef65cc4aa1a29204ba8d639aa859 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Thu, 9 Feb 2017 06:54:48 +0100
Subject: [PATCH 23/25] Restructure travis.yml

---
 .travis.yml | 27 +++++++++++++++++++--------
 1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 8e48c3542..3b17c39fc 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,22 +1,29 @@
 # Source: https://github.com/boostorg/hana/blob/master/.travis.yml
 
+# Sudo is required for installing recent versions of dependencies.
+sudo: required
+
+# Use C++ build environment.
 language: cpp
-sudo: true
+
+# Creates a matrix build job to build the product with the different compilers.
 compiler:
     - clang
     - gcc
-addons:
-    apt:
-        sources:
-            - ubuntu-toolchain-r-test
+
+# Cache dependencies to speed up the build.
 cache:
     directories:
         - ${TRAVIS_BUILD_DIR}/deps/cmake
         - ${TRAVIS_BUILD_DIR}/deps/protobuf
-install:
+
+# Handle dependencies in separate directory.
+before_install:
     - DEPS_DIR="${TRAVIS_BUILD_DIR}/deps"
-    - mkdir -p "${DEPS_DIR}" && cd "${DEPS_DIR}"
+    - mkdir -p "${DEPS_DIR}"
+    - cd "${DEPS_DIR}"
 
+install:
     # Install a recent version of CMake
     - |
         CMAKE_URL="https://cmake.org/files/v3.7/cmake-3.7.2-Linux-x86_64.tar.gz"
@@ -32,9 +39,13 @@ install:
         cd protobuf
         ./configure --prefix=/usr
         make
-        make install
+        sudo make install
+
+# Change directory back to default build directory.
 before_script:
     - cd "${TRAVIS_BUILD_DIR}"
+
+# Run the build script.
 script:
     - mkdir build
     - cd build

From b4ce6eb8c93db7cd13389c76e86443926bf94f40 Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Thu, 9 Feb 2017 07:11:10 +0100
Subject: [PATCH 24/25] Use only g++ compiler

---
 .travis.yml | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 3b17c39fc..b58b58273 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,9 +6,8 @@ sudo: required
 # Use C++ build environment.
 language: cpp
 
-# Creates a matrix build job to build the product with the different compilers.
+# Protobuf requires g++ (see https://github.com/google/protobuf/blob/master/src/README.md)
 compiler:
-    - clang
     - gcc
 
 # Cache dependencies to speed up the build.

From f8394f71478fb03c64fedc30cb1c2e6c9aab1c1f Mon Sep 17 00:00:00 2001
From: Manuel Binna <manuel@binna.de>
Date: Thu, 9 Feb 2017 07:38:29 +0100
Subject: [PATCH 25/25] Always use mkdir -p

This inhibits warnings when the directory to be created already exists.
---
 .travis.yml | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index b58b58273..f01f80edf 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -26,14 +26,14 @@ install:
     # Install a recent version of CMake
     - |
         CMAKE_URL="https://cmake.org/files/v3.7/cmake-3.7.2-Linux-x86_64.tar.gz"
-        mkdir cmake
+        mkdir -p cmake
         travis_retry wget --no-check-certificate --quiet -O - ${CMAKE_URL} | tar --strip-components=1 -xz -C cmake
         export PATH=${DEPS_DIR}/cmake/bin:${PATH}
 
     # Install a recent version of the Protobuf
     - |
         PROTOBUF_URL="https://github.com/google/protobuf/releases/download/v3.2.0/protobuf-cpp-3.2.0.tar.gz"
-        mkdir protobuf
+        mkdir -p protobuf
         travis_retry wget --no-check-certificate --quiet -O - ${PROTOBUF_URL} | tar --strip-components=1 -xz -C protobuf
         cd protobuf
         ./configure --prefix=/usr
@@ -46,7 +46,7 @@ before_script:
 
 # Run the build script.
 script:
-    - mkdir build
+    - mkdir -p build
     - cd build
     - cmake ..
     - cmake --build .