C++ version problem?

[Tsbuild74]

I have no idea how to fix this. I have checked the Issues and tried to solve it like #241 but still had the error like c++ version things. Here's the information about the error:

Compiling absl/log/internal/conditions.cc failed: (Exit 1): gcc failed: error executing command /usr/bin/gcc -U_FORTIFY_SOURCE -fstack-protector -Wall -Wunused-but-set-parameter -Wno-free-nonheap-object -fno-omit-frame-pointer '-std=c++0x' -MD -MF ... (remaining 32 arguments skipped)

Use --sandbox_debug to see verbose messages from the sandbox
In file included from external/com_google_absl/absl/base/config.h:92:0,
from external/com_google_absl/absl/base/attributes.h:37,
from external/com_google_absl/absl/log/internal/conditions.h:36,
from external/com_google_absl/absl/log/internal/conditions.cc:15:
external/com_google_absl/absl/base/policy_checks.h:79:2: error: #error "C++ versions less than C++14 are not supported."
#error "C++ versions less than C++14 are not supported."
^~~~~
Target //:deepmind_lab.so failed to build
Use --verbose_failures to see the command lines of failed build steps.

So how can i solve this problem?

[tkoeppe]

What's your Bazel version? Can you make sure you're using a recent one? And also a recent compiler, or in any case make sure you pass -std=c++14 (or higher) as a compiler flag. Newer compilers will default to C++14 or higher, but older compilers might also support it, but need an explicit switch.

You can also tell Bazel to use our https://github.com/google-deepmind/lab/blob/master/.precommit.bazelrc, say via:

bazel --bazelrc=.precommit.bazelrc build [etc etc]

As you can see, we're setting -std=c++17 globally in the bazelrc file.

Or build with --cxxopt=-std=c++14.