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A technical blog post examines how GCC translates C switch statements into machine code, going beyond simple decision trees. It shows GCC building jump tables for compact case values, including cases offset by a constant, and notes that most of these optimizations also apply to clang except for one technique called bitset lowering.
A Windows 11 Insider build (29295) spotted by Neowin includes a new 'Advanced Performance Extensions (APX)' setting, though no Intel chips currently support the feature. Intel first detailed APX in 2023, describing 32 general-purpose registers and new instruction formats meant to cut loads by 10% and stores by 20% versus its baseline Intel 64 architecture.
A developer's personal blog post demonstrates that GCC 16.2, when compiling C code that triggers undefined behavior (via std::unreachable() or a null pointer dereference), can generate assembly that executes a completely separate, never-called function. In one example, writing to a 'device_command' variable followed by undefined behavior causes the compiler to also emit code for an unrelated 'explode()' function that was never invoked in the source.
Kpler data shows GCC states now export about 24 million barrels per day, surpassing pre-war volumes, with roughly 14 million bpd moving through the U.S.-protected shipping lane in the Strait of Hormuz. Iran remains excluded from this trade under a continuing U.S. Navy blockade, while hundreds of tankers, including a short-haul 'Hormuz Shuttle Service,' keep crude flowing despite periodic drone and missile strikes.
A technical blog post lists concrete cases where GCC and Clang do not conform to the ISO C standard by default, including treatment of the asm keyword as a reserved extension and GCC's hardcoded FLT_ROUNDS macro that ignores runtime rounding-mode changes via fesetround. The author also flags unfinished coverage of the standard's five floating-point pragmas as an area of ongoing non-conformance.
Edison Design Group has published its EDG C/C++ compiler front end as an open source project on GitHub, including a C-generating back end, a C++-generating back end, a prelinker, a runtime support library, and related development tools. The project also ships documentation and guides covering building the compiler, contributing changes, and setting up a development environment.
At Black Hat USA, security researcher Chris Domas told David Bombal that compilers can legally strip out security-critical operations like memory-clearing code, even when source code follows best practices. He demonstrated how subtle factors such as data size, register pressure and structure layout can determine whether an optimized binary is safe or exploitable, with some byte sizes producing secure code and nearby sizes producing vulnerable output.
Martin Uecker details how GCC compiles nested functions that access variables from an enclosing function, explaining that such functions are lowered early in the middle-end. Variables referenced by the nested function are gathered into a single synthetic struct, with a pointer to that struct passed to the nested function instead of using older stack-frame-pointer techniques like those in Pascal.
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.