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Diffstat (limited to 'ports/unix/README.md')
| -rw-r--r-- | ports/unix/README.md | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/ports/unix/README.md b/ports/unix/README.md index b7aa6e3fef..656d4303d3 100644 --- a/ports/unix/README.md +++ b/ports/unix/README.md @@ -155,3 +155,21 @@ The default compiler optimisation level is -Os, or -Og if `DEBUG=1` is set. Setting the variable `COPT` will explicitly set the optimisation level. For example `make [other arguments] COPT=-O0 DEBUG=1` will build a binary with no optimisations, assertions enabled, and debug symbols. + +### Sanitizers + +Sanitizers are extra runtime checks supported by gcc and clang. The CI process +supports building with the "undefined behavior" (UBSan) or "address" (ASan) +sanitizers. The script `tools/ci.sh` is the source of truth about how to build +and run in these modes. + +Several classes of checks are disabled via compiler flags: + +* In the undefined behavior sanitizer, checks based on the presence of the + `non_null` attribute are disabled because the code makes technically incorrect + calls like `memset(NULL, 0, 0)`. A future C standard is likely to permit such + calls. +* In the address sanitizer, `detect_stack_use_after_return` is disabled. This + check is intended to make sure locals in a "returned from" stack frame are not + used. However, this mode interferes with various assumptions that + MicroPython's stack checking, NLR, and GC rely on. |