Does anyone know how to start debugging this Rust bindgen indent issue?
stderr thread 'main' panicked at '"vpx_codec_ctx_union_(unnamed_at_/usr/include/vpx/_/vpx_codec_h_206_3)" is not a valid Ident', /home/ignis/.cargo/registry/src/github.com-1ecc6299db9ec823/proc-macro2-1.0.59/src/fallback.rs:811:9
This is referencing this part of the libvpx header:
/*!\brief Codec context structure
*
* All codecs \ref MUST support this context structure fully. In general,
* this data should be considered private to the codec algorithm, and
* not be manipulated or examined by the calling application. Applications
* may reference the 'name' member to get a printable description of the
* algorithm.
*/
typedef struct vpx_codec_ctx {
const char *name; /**< Printable interface name */
vpx_codec_iface_t *iface; /**< Interface pointers */
vpx_codec_err_t err; /**< Last returned error */
const char *err_detail; /**< Detailed info, if available */
vpx_codec_flags_t init_flags; /**< Flags passed at init time */
union {
/**< Decoder Configuration Pointer */
const struct vpx_codec_dec_cfg *dec;
/**< Encoder Configuration Pointer */
const struct vpx_codec_enc_cfg *enc;
const void *raw;
} config; /**< Configuration pointer aliasing union */
vpx_codec_priv_t *priv; /**< Algorithm private storage */
} vpx_codec_ctx_t;
I see a lot of answers online talking about blacklisting these types, but I can't blacklist this as the context type is needed. It seems like the union type is causing trouble...
Update: Found the relevant part of the vpx-sys docs: https://docs.rs/env-libvpx-sys/5.1.2/vpx_sys
Seems like the library author was able to generate the bindings...
This is the panicking code:
pub(crate) fn is_ident_start(c: char) -> bool {
c == '_' || unicode_ident::is_xid_start(c)
}
pub(crate) fn is_ident_continue(c: char) -> bool {
unicode_ident::is_xid_continue(c)
}
fn validate_ident(string: &str, raw: bool) {
if string.is_empty() {
panic!("Ident is not allowed to be empty; use Option<Ident>");
}
if string.bytes().all(|digit| digit >= b'0' && digit <= b'9') {
panic!("Ident cannot be a number; use Literal instead");
}
fn ident_ok(string: &str) -> bool {
let mut chars = string.chars();
let first = chars.next().unwrap();
if !is_ident_start(first) {
return false;
}
for ch in chars {
if !is_ident_continue(ch) {
return false;
}
}
true
}
if !ident_ok(string) {
panic!("{:?} is not a valid Ident", string);
}
if raw {
match string {
"_" | "super" | "self" | "Self" | "crate" => {
panic!("`r#{}` cannot be a raw identifier", string);
}
_ => {}
}
}
}
This is just checking if the identifiers have valid characters in them. In this case, (
(and I suspect /
) are invalid characters.
So why is this happening? Take a look at the error message: "vpx_codec_ctx_union_(unnamed_at_/usr/include/vpx/_/vpx_codec_h_206_3)" is not a valid Ident
Everything in the (unamed...)
part shouldn't've gotten to this stage. Doing a search, we find the rust-bindgen issue on this which references the libclang commit that caused the change.
Specifically, that commit was for Clang 16. Therefore, either downgrade Clang to a version before 16, or update your bindgen crate to v0.62.0 or above (which is when the fix was applied).