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Tech News
C++ Insights is a Clang-based source-to-source transformation tool that exposes implicit compiler behavior, such as auto-generated constructors, copy assignment operators, and type casts, directly in readable C++ syntax. Its creator built the tool after researching modern C++11/14/17 features like lambdas and structured bindings, aiming to make hidden compiler operations visible to developers.
The upcoming C++26 standard, via proposal P2809R3, changes the language so that trivial infinite loops like 'while(true);' are no longer undefined behavior. Previously, compilers such as Clang could legally assume such loops terminate and optimize them away entirely, sometimes causing code after the loop to execute unexpectedly. Because the fix was also accepted as a defect report, compiler vendors may backport it to earlier C++ standard modes too.
A technical blog post by Martin Uecker examines how GCC compiles nested functions using trampolines placed on the stack, which normally require the stack to be executable. He shows that by extracting the code address and static chain values embedded in the trampoline and passing them to the __builtin_call_with_static_chain built-in, developers can indirectly call nested functions on older GCC versions without needing an executable stack.