diff options
Diffstat (limited to 'compiler/rustc_session/src/session.rs')
| -rw-r--r-- | compiler/rustc_session/src/session.rs | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/compiler/rustc_session/src/session.rs b/compiler/rustc_session/src/session.rs index 8386fe8dab0..85bd8340c3c 100644 --- a/compiler/rustc_session/src/session.rs +++ b/compiler/rustc_session/src/session.rs @@ -776,8 +776,15 @@ impl Session { pub fn must_emit_unwind_tables(&self) -> bool { // This is used to control the emission of the `uwtable` attribute on - // LLVM functions. + // LLVM functions. The `uwtable` attribute according to LLVM is: // + // This attribute indicates that the ABI being targeted requires that an + // unwind table entry be produced for this function even if we can show + // that no exceptions passes by it. This is normally the case for the + // ELF x86-64 abi, but it can be disabled for some compilation units. + // + // Typically when we're compiling with `-C panic=abort` we don't need + // `uwtable` because we can't generate any exceptions! // Unwind tables are needed when compiling with `-C panic=unwind`, but // LLVM won't omit unwind tables unless the function is also marked as // `nounwind`, so users are allowed to disable `uwtable` emission. |