rust-lang / rust-lang/rustc_codegen_gcc
Integer width is asumed to be 32 bit at some points
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Description
I'm building for a target that has an int width of 16 bit. Compilation fails at some points, because an integer width of 32 bit is assumed.
Here (and similar builtins just below): https://github.com/rust-lang/rustc_codegen_gcc/blob/9aec231fbaf09ecd9ee6350100045cfccd4f4689/src/int.rs#L277-L291
__builtin_s/uadd_overflow takes ints, but on my platform they are only 16 bit long.
memset takes an int, but the fill_byte is hardcoded to i32.
(PS: Thank you for your work! This project makes it possible to use rust on my architecture at all <3 )
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
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- Open a pull request that references the issue number.
Research direction
Start in src/int.rs around lines 277–291 and src/builder.rs around lines 1388–1393, then reproduce the failure for a target with a 16-bit int width. Check the integer types passed to the __builtin_s/uadd_overflow variants and to memset. Done means these paths no longer assume 32-bit ints and compilation succeeds for the affected target.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- rust
- Domain
- compilers
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100