build error "could not bind to an lvalue of type 'const char [41]'"

[pureland]

Instructions
Please include a detailed Title above. Next, please complete the following sections below:

• Build Error
  Reference to type 'const std::string' (aka 'const basic_string<char, char_traits<char>, allocator<char> >') could not bind to an lvalue of type 'const char [41]'

• Build Environment
  Xcode Version 10.1 (10B61)/ clang version 4.0.1 (tags/RELEASE_401/final)

• Console Logs (optional)

bitshares-core/libraries/fc/include/fc/variant.hpp:571:10: error: reference to type 'const std::string' (aka 'const basic_string<char, char_traits<char>,
      allocator<char> >') could not bind to an lvalue of type 'const char [41]'
         _FC_ASSERT( max_depth > 0, "Recursion depth exceeded!" );
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Build Environment
Details about the build environment, including the relevant required libraries. Much of this information can be found in the CMakeFiles/CMakeOutput.log.

• Host OS: macOS Mojave
• Host Physical RAM 32GB
• Source Branch/Tag: master
• OpenSSL Version: 1.1.0g
• Boost Version: 1.59
• C++ Compiler: clang version 4.0.1 (tags/RELEASE_401/final)

[pmconrad]

Thanks. Can you please check if the error also occurs in the latest testnet release?
Need to

git checkout test-3.3.1
git submodule update --init --recursive
make

inside your checked out core directory.

[pmconrad]

@pureland @jmjatlanta could you test if this change fixes the problem: bitshares/bitshares-fc@78ffb6d ?

[jmjatlanta]

@pureland @jmjatlanta could you test if this change fixes the problem: bitshares/bitshares-fc@78ffb6d ?

I am unable to replicate the problem on my mac. I will take a look at my environment and see if I can cause it.

[jmjatlanta]

What about fc::throw_assertion_failure( std::string(#cond) + ": " + msg);

Perhaps a bit more readable. Just my opinion. I have been unable to cause the problem. I now have multiple versions of clang. Perhaps cmake is not calling the (older) clang version I am expecting.

[pmconrad]

Not that it matters much, but that's two runtime-concatenations of strings, whereas mine is just a string literal.

[pmconrad]

Fixed with #1949