Why Does Calling C Functions from C++ Always Result in Undefined Reference?

Why Does Calling C Functions from C++ Always Result in Undefined Reference?

In embedded development, we often encounter a situation where: the underlying driver library is written in C language (<span><span>.c</span></span> file), while the upper application or framework is in C++ (<span><span>.cpp</span></span> file). As a result, when we call it, we get: undefined reference to `xxx_function' Clearly, it is declared in the <span><span>.h</span></span> file and implemented in … Read more

A Comprehensive Analysis of C++ Compilation and Linking: How to Resolve Those Frustrating ‘Undefined References’

A Comprehensive Analysis of C++ Compilation and Linking: How to Resolve Those Frustrating 'Undefined References'

Have you ever encountered these “mysterious” issues: clearly, both .cpp and .h files are written, compilation passes, but linking fails with the error message undefined reference to SomeFunction()? You have implemented merging with others’ projects, linking libraries, writing CMakeLists, and Makefiles, yet it always mysteriously fails once the project files are involved…