Use –whole-archive linker option. Libraries that come after it in the command line will not have unreferenced symbols discarded. You can resume normal linking behaviour by adding –no-whole-archive after these libraries. In your example, the command will be: g++ -o program main.o -Wl,–whole-archive /path/to/libmylib.a In general, it will be: g++ -o program main.o \ -Wl,–whole-archive … Read more
Today I have bumped into this problem and solved it in the following way. I pressed “Reset defaults” button everywhere I could find it in Eclipse settings (for example, Preferences/C++/Build/Settings/Discovery). After that the error disappeared and the code compiled successfully.
Check the type you are deriving the enum class from exists. In this case, there was no typedef specified for int8.
On high optimization levels, the compiler can eliminate intermediate values, as you have seen here. There are a number of options: You can reduce the optimization level to make it easier for the debugger to keep track of things. -O0 is certain to work (but will be quite a lot slower), -O1 might work okay … Read more
you may want to specify the C++ version with g++ -std=c++11 tmp.cpp -o tmp I don’t have gcc 4.8.1 at hand , but in older versions of GCC, you can use g++ -std=c++0x tmp.cpp -o tmp At least gcc 4.9.2 I believe also support part of C++14 by specifying g++ -std=c++1y tmp.cpp -o tmp Update: … Read more
To get a useful compile time name: Supposing you have some unknown type named ‘T’. You can get the compiler to print it’s type by using it horribly. For example: typedef typename T::something_made_up X; The error message will be like: error: no type named ‘something_made_up’ in ‘Wt::Dbo::ptr<trader::model::Candle>’ The bit after ‘in’ shows the type. (Only … Read more
The solution is to add the option -Wa,-mbig-obj if your version of GCC supports that option. You probably only need it during the compilation step, not the linker step. If your compiler does not support that option, you should look into using mingw-w64 and MSYS2.
Paolo Carlini, a GCC/libstdc++ contributor, confirmed it is a bug/regression.
The standard says in [temp.res]/8 No diagnostic shall be issued for a template definition for which a valid specialization can be generated. If no valid specialization can be generated for a template definition, and that template is not instantiated, the template definition is ill-formed, no diagnostic required. … [ Note: If a template is instantiated, … Read more
Drop the ‘s’ off of the package name. You want sudo apt-get install build-essential You may also need to run sudo apt-get update to make sure that your package index is up to date. For anyone wondering why this package may be needed as part of another install, it contains the essential tools for building … Read more