d82219a4fa
Previously, we unconditionally set the bitwidth to 128-bits, the largest an discrimnator would possibly be. Then, LLVM would cut down the constant by chopping off leading zeroes before emitting the DWARF. LLVM only supported 64-bit descriminators, so this would also have occasionally resulted in truncated data (or an assert) if more than 64-bits were used. LLVM added support for 128-bit enumerators in llvm/llvm-project#125578 That patchset also trusts the constant to describe how wide the variant tag is. As a result, we went from emitting tags that looked like: DW_AT_discr_value (0xfe) (`form1`) to emitting tags that looked like: DW_AT_discr_value (<0x10> fe ff ff ff 00 00 00 00 00 00 00 00 00 00 00 00 ) This makes the `DW_AT_discr_value` encode at the bitwidth of the tag, which: 1. Is probably closer to our intentions in terms of describing the data. 2. Doesn't invoke the 128-bit support which may not be supported by all debuggers / downstream tools. 3. Will result in smaller debug information. |
||
|---|---|---|
| .. | ||
| metadata | ||
| create_scope_map.rs | ||
| doc.md | ||
| dwarf_const.rs | ||
| gdb.rs | ||
| metadata.rs | ||
| mod.rs | ||
| namespace.rs | ||
| utils.rs | ||