Add the --emit-diagnostics flag (#2436)

* Add the `--emit-diagnostics` flag * remove test * add(diagnostics): var.rs and lib.rs module have a function each * add(diagnostics): rustfmt * add(diagnostics): docs moved to book * add(diagnostics): wip, saving location * add(diagnostics): wip, saving location * add(diagnostics): add line number and origin file to slice * add(diagnostics): unused var name cleanup * revert(diagnostics): changes to line number, before merging Christian's * Add API for slice locations * Emit diagnostic for unsupported ABIs * add(diagnostics): line number and file names to diagnostics * chore: fmt * add(diagnostics): label to say 'from bindgen' * add(diagnostics): add_footer, add a warning with footer info * add(diagnostics): add a warning with footer info * add(diagnostics): add a warning in the Diagnostics instead of copying everywhere * Remove IDs that are not shown and use `diagnostic` instead of `warning` * Remove unused function * Deduplciate log entry * Introduce `Level` * Fix clippy warning * Simplify duplicated macro diagnostic * Unify source extraction * Simplify non-fatal rustfmt error diagnostic * Print all diagnostic lines when using `cargo:warning` * Put all the diagnostic logic under the experimental flag * Avoid `bool` parameters * Clean rebase debris * Disable duplicated macros warning for now * Emit warning when using a deprecated Rust target * Document the `emit_diagnostics` method * Update Changelog * Remove diagnostics section from book. Diagnostics are prone to change so keeping the book up to date might require some automation. * Run rustfmt * Fix clippy warning * Remove file added by accident --------- Co-authored-by: Amanjeev Sethi <aj@amanjeev.com>
rust-lang · Apr 3, 2023 · 2ab66fd · 2ab66fd
1 parent 040149b
commit 2ab66fd
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Showing 12 changed files with 615 additions and 83 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -171,6 +171,9 @@
    which tool will be used to format the bindings. The
    `Formatter::Prettyplease`   variant is only available if the
    `"prettyplease"` feature is enabled. 
+ * Added the `Builder::emit_diagnostics` method and the  `--emit-diagnostics`
+   flag to enable emission of diagnostic messages.
+
 ## Changed
  * Static functions with no arguments use `void` as their single argument
    instead of having no arguments when the `--wrap-static-fns` flag is used.
@@ -187,6 +190,8 @@
  * The following deprecated flags were removed: `--use-msvc-mangling`,
    `--rustfmt-bindings` and `--size_t-is-usize`.
  * The `--no-rustfmt-bindings` flag was removed in favor of `--formatter=none`.
+ * The `Bindings::emit_warnings` and `Bindings::warnings` methods were removed
+   in favor of `--emit-diagnostics`.
 
 ## Fixed
 

diff --git a/Cargo.lock b/Cargo.lock
diff --git a/bindgen-cli/options.rs b/bindgen-cli/options.rs
@@ -369,6 +369,9 @@ struct BindgenCommand {
     /// bitfields. This flag is ignored if the `--respect-cxx-access-specs` flag is used.
     #[arg(long, value_name = "VISIBILITY")]
     default_visibility: Option<FieldVisibilityKind>,
+    /// Whether to emit diagnostics or not.
+    #[arg(long, requires = "experimental")]
+    emit_diagnostics: bool,
     /// Enables experimental features.
     #[arg(long)]
     experimental: bool,
@@ -495,6 +498,7 @@ where
         wrap_static_fns_path,
         wrap_static_fns_suffix,
         default_visibility,
+        emit_diagnostics,
         experimental: _,
         version,
         clang_args,
@@ -997,12 +1001,25 @@ where
         }
     }
 
-    for (custom_derives, kind) in [
-        (with_derive_custom, None),
-        (with_derive_custom_struct, Some(TypeKind::Struct)),
-        (with_derive_custom_enum, Some(TypeKind::Enum)),
-        (with_derive_custom_union, Some(TypeKind::Union)),
+    for (custom_derives, kind, name) in [
+        (with_derive_custom, None, "--with-derive-custom"),
+        (
+            with_derive_custom_struct,
+            Some(TypeKind::Struct),
+            "--with-derive-custom-struct",
+        ),
+        (
+            with_derive_custom_enum,
+            Some(TypeKind::Enum),
+            "--with-derive-custom-enum",
+        ),
+        (
+            with_derive_custom_union,
+            Some(TypeKind::Union),
+            "--with-derive-custom-union",
+        ),
     ] {
+        let name = emit_diagnostics.then(|| name);
         for custom_derive in custom_derives {
             let (regex, derives) = custom_derive
                 .rsplit_once('=')
@@ -1011,7 +1028,7 @@ where
 
             let mut regex_set = RegexSet::new();
             regex_set.insert(regex);
-            regex_set.build(false);
+            regex_set.build_with_diagnostics(false, name);
 
             builder = builder.parse_callbacks(Box::new(CustomDeriveCallback {
                 derives,
@@ -1037,5 +1054,9 @@ where
         builder = builder.default_visibility(visibility);
     }
 
+    if emit_diagnostics {
+        builder = builder.emit_diagnostics();
+    }
+
     Ok((builder, output, verbose))
 }
diff --git a/bindgen-tests/tests/tests.rs b/bindgen-tests/tests/tests.rs
@@ -672,22 +672,6 @@ fn dump_preprocessed_input() {
     );
 }
 
-#[test]
-fn allowlist_warnings() {
-    let header = concat!(
-        env!("CARGO_MANIFEST_DIR"),
-        "/tests/headers/allowlist_warnings.h"
-    );
-
-    let bindings = builder()
-        .header(header)
-        .allowlist_function("doesnt_match_anything")
-        .generate()
-        .expect("unable to generate bindings");
-
-    assert_eq!(1, bindings.warnings().len());
-}
-
 fn build_flags_output_helper(builder: &bindgen::Builder) {
     let mut command_line_flags = builder.command_line_flags();
     command_line_flags.insert(0, "bindgen".to_string());

diff --git a/bindgen/Cargo.toml b/bindgen/Cargo.toml
@@ -35,7 +35,8 @@ quote = { version = "1", default-features = false }
 syn = { version = "2.0", features = ["full", "extra-traits", "visit-mut"]}
 regex = { version = "1.5", default-features = false , features = ["std", "unicode"] }
 which = { version = "4.2.1", optional = true, default-features = false }
-prettyplease = { version = "0.2.0", optional = true}
+prettyplease = { version = "0.2.0", optional = true }
+annotate-snippets = { version = "0.9.1", features = ["color"], optional = true }
 shlex = "1"
 rustc-hash = "1.0.1"
 proc-macro2 = { version = "1", default-features = false }
@@ -49,7 +50,7 @@ runtime = ["clang-sys/runtime"]
 # Dynamically discover a `rustfmt` binary using the `which` crate
 which-rustfmt = ["which"]
 __cli = []
-experimental = []
+experimental = ["annotate-snippets"]
 
 # These features only exist for CI testing -- don't use them if you're not hacking
 # on bindgen!

diff --git a/bindgen/codegen/mod.rs b/bindgen/codegen/mod.rs
@@ -4213,23 +4213,43 @@ impl CodeGenerator for Function {
             ClangAbi::Known(Abi::ThisCall)
                 if !ctx.options().rust_features().thiscall_abi =>
             {
-                warn!("Skipping function with thiscall ABI that isn't supported by the configured Rust target");
+                unsupported_abi_diagnostic::<false>(
+                    name,
+                    item.location(),
+                    "thiscall",
+                    ctx,
+                );
                 return None;
             }
             ClangAbi::Known(Abi::Vectorcall)
                 if !ctx.options().rust_features().vectorcall_abi =>
             {
-                warn!("Skipping function with vectorcall ABI that isn't supported by the configured Rust target");
+                unsupported_abi_diagnostic::<false>(
+                    name,
+                    item.location(),
+                    "vectorcall",
+                    ctx,
+                );
                 return None;
             }
             ClangAbi::Known(Abi::CUnwind)
                 if !ctx.options().rust_features().c_unwind_abi =>
             {
-                warn!("Skipping function with C-unwind ABI that isn't supported by the configured Rust target");
+                unsupported_abi_diagnostic::<false>(
+                    name,
+                    item.location(),
+                    "C-unwind",
+                    ctx,
+                );
                 return None;
             }
             ClangAbi::Known(Abi::Win64) if signature.is_variadic() => {
-                warn!("Skipping variadic function with Win64 ABI that isn't supported");
+                unsupported_abi_diagnostic::<true>(
+                    name,
+                    item.location(),
+                    "Win64",
+                    ctx,
+                );
                 return None;
             }
             ClangAbi::Unknown(unknown_abi) => {
@@ -4316,6 +4336,51 @@ impl CodeGenerator for Function {
     }
 }
 
+fn unsupported_abi_diagnostic<const VARIADIC: bool>(
+    fn_name: &str,
+    location: Option<&crate::clang::SourceLocation>,
+    abi: &str,
+    ctx: &BindgenContext,
+) {
+    warn!(
+        "Skipping {}function `{}` with the {} ABI that isn't supported by the configured Rust target",
+        if VARIADIC { "variadic " } else { "" },
+        fn_name,
+        abi
+    );
+
+    #[cfg(feature = "experimental")]
+    if ctx.options().emit_diagnostics {
+        use crate::diagnostics::{get_line, Diagnostic, Level, Slice};
+
+        let mut diag = Diagnostic::default();
+        diag
+        .with_title(format!(
+                "The `{}` {}function uses the {} ABI which is not supported by the configured Rust target",
+                fn_name,
+                if VARIADIC { "variadic " } else { "" },
+                abi), Level::Warn)
+            .add_annotation("No code will be generated for this function.", Level::Warn)
+            .add_annotation(format!("The configured Rust version is {}.", String::from(ctx.options().rust_target)), Level::Note);
+
+        if let Some(loc) = location {
+            let (file, line, col, _) = loc.location();
+
+            if let Some(filename) = file.name() {
+                if let Ok(Some(source)) = get_line(&filename, line) {
+                    let mut slice = Slice::default();
+                    slice
+                        .with_source(source)
+                        .with_location(filename, line, col);
+                    diag.add_slice(slice);
+                }
+            }
+        }
+
+        diag.display()
+    }
+}
+
 fn objc_method_codegen(
     ctx: &BindgenContext,
     method: &ObjCMethod,
@@ -4586,8 +4651,7 @@ impl CodeGenerator for ObjCInterface {
 
 pub(crate) fn codegen(
     context: BindgenContext,
-) -> Result<(proc_macro2::TokenStream, BindgenOptions, Vec<String>), CodegenError>
-{
+) -> Result<(proc_macro2::TokenStream, BindgenOptions), CodegenError> {
     context.gen(|context| {
         let _t = context.timer("codegen");
         let counter = Cell::new(0);