Build GDB with different compilers
In general, it is good to keep GDB built by different popular compilers, so people are easy to build GDB and different warnings from different compilers will catch more bugs in GDB. On the other hand, GCC is still the primary compiler to build GDB, and support of other compilers in building GDB should not undermine the case that GDB is built by GCC nor degrade the code quality. For example, it is not acceptable to build GDB with compiler X but break the build with GCC. We still must fix the GDB build failure with GCC, as what we did in the past, and we welcome the contributions to fix the GDB build with other compilers.
Ideally, every bug that other compilers find in the GDB source code that GCC didn't warn about should be considered as a GCC bug, and we should make sure that it's reported on the GCC tracker.