travis_clang_cpp14

Branch
master
develop

This GitHub is part of the Travis C++ Tutorial.

The goal of this project is to have a clean Travis CI build, with specs:

• Build system: none
• C++ compiler: clang
• C++ version: C++14
• Libraries: STL only
• Code coverage: none
• Source: one single file, main.cpp

More complex builds:

• Add GCC: travis_clang_gcc_cpp14
• Add qmake: travis_qmake_clang_cpp14

Equally complex builds:

• Replace clang by GCC: travis_qmake_gcc_cpp14

Less complex builds:

• Use of C++98: travis_clang_cpp98
• Use of C++11: travis_clang_cpp11

Troubleshooting

no member named 'gets' in the global namespace

Caused by:

clang++-3.8 -o main -std=c++14 main.cpp

The error message is rather clear:

In file included from main.cpp:1:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/iostream:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/ostream:38:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/ios:42:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/ios_base.h:41:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/locale_classes.h:40:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/string:52:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/bits/basic_string.h:2815:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/ext/string_conversions.h:43:
/usr/bin/../lib/gcc/x86_64-linux-gnu/4.8/../../../../include/c++/4.8/cstdio:120:11: error: 
      no member named 'gets' in the global namespace
  using ::gets;
        ~~^
1 error generated.

The STL from GCC-4.8 is released somewhere from March 2013 (4.8.0) and June 2015 (4.8.5). There is a cha

Solutions:

• Use libc++ as STL, by using clang++ -std=c++14 -stdlib=libc++ my_main.cpp

Background:

• Similar compiler error: http://stackoverflow.com/questions/17775390/clang-3-3-in-c1y-mode-cannot-parse-cstdio-header
• Bugfix of this compiler error: https://bugs.launchpad.net/ubuntu/+source/llvm-toolchain-3.6/+bug/1620181/comments/2
• Using libc++: http://libcxx.llvm.org/docs/UsingLibcxx.html

'iostream' file not found

Caused by:

clang++-3.8 -o main -std=c++14 -stdlib=libc++ main.cpp

main.cpp:1:10: fatal error: 'iostream' file not found
#include <iostream>
         ^
1 error generated.

Solution (from http://stackoverflow.com/a/31488490):

In the travis.yml, add:

sudo apt-get install -y libc++-dev libc++abi-dev

A suitable spot is the install: section. If that section is absent, add:

install:
  - sudo apt-get install -y libc++-dev libc++abi-dev

cannot find -lc++

Caused by:

clang++ -o main -std=c++14 -stdlib=libc++ main.cpp

Error message:

/usr/bin/ld: cannot find -lc++
clang: error: linker command failed with exit code 1 (use -v to see invocation)
The command "clang++ -o main -std=c++14 -stdlib=libc++ main.cpp" exited with 1.

Solution:

In the travis.yml, add:

sudo apt-get install -y libc++-dev libc++abi-dev

A suitable spot is the install: section. If that section is absent, add:

install:
  - sudo apt-get install -y libc++-dev libc++abi-dev