From 08a1c566a792dcf9657d293155f7ada87746bb65 Mon Sep 17 00:00:00 2001 From: Tomasz Miąsko Date: Mon, 27 Jan 2020 00:00:00 +0000 Subject: Detect use-after-scope bugs with AddressSanitizer Enable use-after-scope checks by default when using AddressSanitizer. They allow to detect incorrect use of stack objects after their scope have already ended. The detection is based on LLVM lifetime intrinsics. To facilitate the use of this functionality, the lifetime intrinsics are now emitted regardless of optimization level if enabled sanitizer makes use of them. --- src/librustc_codegen_llvm/builder.rs | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) (limited to 'src/librustc_codegen_llvm') diff --git a/src/librustc_codegen_llvm/builder.rs b/src/librustc_codegen_llvm/builder.rs index 357b0b6c451..c59b81eb4cc 100644 --- a/src/librustc_codegen_llvm/builder.rs +++ b/src/librustc_codegen_llvm/builder.rs @@ -7,7 +7,7 @@ use crate::type_of::LayoutLlvmExt; use crate::value::Value; use libc::{c_char, c_uint}; use log::debug; -use rustc::session::config; +use rustc::session::config::{self, Sanitizer}; use rustc::ty::layout::{self, Align, Size, TyLayout}; use rustc::ty::{self, Ty, TyCtxt}; use rustc_codegen_ssa::base::to_immediate; @@ -1232,12 +1232,19 @@ impl Builder<'a, 'll, 'tcx> { } fn call_lifetime_intrinsic(&mut self, intrinsic: &str, ptr: &'ll Value, size: Size) { - if self.cx.sess().opts.optimize == config::OptLevel::No { + let size = size.bytes(); + if size == 0 { return; } - let size = size.bytes(); - if size == 0 { + let opts = &self.cx.sess().opts; + let emit = match opts.debugging_opts.sanitizer { + // Some sanitizer use lifetime intrinsics. When they are in use, + // emit lifetime intrinsics regardless of optimization level. + Some(Sanitizer::Address) | Some(Sanitizer::Memory) => true, + _ => opts.optimize != config::OptLevel::No, + }; + if !emit { return; } -- cgit 1.4.1-3-g733a5