Not running or not compiling? I've often had issues with compiling, either because of unwarranted assumptions in the third-party projects or because glibc made

Not running or not compiling? I've often had issues with compiling, either because of unwarranted assumptions in the third-party projects or because glibc made changes to their absurdly complex naming and feature gating hacks in their header files. But glibc uses symbol versioning so even if the prototype of function foo changes, older software built against version X.Y should still link to fooX.Y at runtime. I don't follow glibc closely enough to know how many times they've accidentally broken things, though. I'm sure it's happened. More complex runtime behaviors, like with the DNS resolver, are definitely common, but usually it's debatable whether glibc is fairly blameworthy.