babaabbcc8
This defines std::unreachable as an assertion for debug mode, a trap when _GLIBCXX_ASSERTIONS is defined, and __builtin_unreachable() otherwise. The reason for only using __builtin_trap() in the second case is to avoid the overhead of setting up a call to __glibcxx_assert_fail that should never happen. UBsan can detect if __builtin_unreachable() is executed, so if a feature test macro for that sanitizer is added, we could change just use __builtin_unreachable() when the sanitizer is enabled. While thinking about what the debug assertion failure should print, I noticed that the __glibcxx_assert_fail function doesn't check for null pointers. This adds a check so we don't try to print them if null. libstdc++-v3/ChangeLog: * include/std/utility (unreachable): Define for C++23. * include/std/version (__cpp_lib_unreachable): Define. * src/c++11/debug.cc (__glibcxx_assert_fail): Check for valid arguments. Handle only the function being given. * testsuite/20_util/unreachable/1.cc: New test. * testsuite/20_util/unreachable/version.cc: New test. |
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| .. | ||
| 17_intro | ||
| 18_support | ||
| 19_diagnostics | ||
| 20_util | ||
| 21_strings | ||
| 22_locale | ||
| 23_containers | ||
| 24_iterators | ||
| 25_algorithms | ||
| 26_numerics | ||
| 27_io | ||
| 28_regex | ||
| 29_atomics | ||
| 30_threads | ||
| abi | ||
| backward | ||
| config | ||
| data | ||
| decimal | ||
| experimental | ||
| ext | ||
| lib | ||
| libstdc++-abi | ||
| libstdc++-dg | ||
| libstdc++-prettyprinters | ||
| libstdc++-xmethods | ||
| performance | ||
| special_functions | ||
| std | ||
| tr1 | ||
| tr2 | ||
| util | ||
| Makefile.am | ||
| Makefile.in | ||