Auto merge of #122359 - Zoxc:missing-static-notes, r=wesleywiser

Print the crates not available as static

This prints out the crates not available to be statically linked when static linking is preferred and we run into an error with duplicated crates.

compiler/rustc_metadata/messages.ftl

@@ -38,6 +38,9 @@ metadata_crate_dep_multiple =
     cannot satisfy dependencies so `{$crate_name}` only shows up once
     .help = having upstream crates all available in one format will likely make this go away
 
+metadata_crate_dep_not_static =
+    `{$crate_name}` was unavailable as a static crate, preventing fully static linking
+
 metadata_crate_location_unknown_type =
     extern location for {$crate_name} is of an unknown type: {$path}
 

compiler/rustc_metadata/src/dependency_format.rs

@@ -54,7 +54,7 @@
 use crate::creader::CStore;
 use crate::errors::{
     BadPanicStrategy, CrateDepMultiple, IncompatiblePanicInDropStrategy, LibRequired,
-    RequiredPanicStrategy, RlibRequired, RustcLibRequired, TwoPanicRuntimes,
+    NonStaticCrateDep, RequiredPanicStrategy, RlibRequired, RustcLibRequired, TwoPanicRuntimes,
 };
 
 use rustc_data_structures::fx::FxHashMap;
@@ -123,13 +123,15 @@ fn calculate_type(tcx: TyCtxt<'_>, ty: CrateType) -> DependencyList {
         CrateType::Rlib => Linkage::NotLinked,
     };
 
+    let mut unavailable_as_static = Vec::new();
+
     match preferred_linkage {
         // If the crate is not linked, there are no link-time dependencies.
         Linkage::NotLinked => return Vec::new(),
         Linkage::Static => {
             // Attempt static linkage first. For dylibs and executables, we may be
             // able to retry below with dynamic linkage.
-            if let Some(v) = attempt_static(tcx) {
+            if let Some(v) = attempt_static(tcx, &mut unavailable_as_static) {
                 return v;
             }
 
@@ -169,11 +171,11 @@ fn calculate_type(tcx: TyCtxt<'_>, ty: CrateType) -> DependencyList {
         let src = tcx.used_crate_source(cnum);
         if src.dylib.is_some() {
             info!("adding dylib: {}", name);
-            add_library(tcx, cnum, RequireDynamic, &mut formats);
+            add_library(tcx, cnum, RequireDynamic, &mut formats, &mut unavailable_as_static);
             let deps = tcx.dylib_dependency_formats(cnum);
             for &(depnum, style) in deps.iter() {
                 info!("adding {:?}: {}", style, tcx.crate_name(depnum));
-                add_library(tcx, depnum, style, &mut formats);
+                add_library(tcx, depnum, style, &mut formats, &mut unavailable_as_static);
             }
         }
     }
@@ -201,7 +203,7 @@ fn calculate_type(tcx: TyCtxt<'_>, ty: CrateType) -> DependencyList {
         {
             assert!(src.rlib.is_some() || src.rmeta.is_some());
             info!("adding staticlib: {}", tcx.crate_name(cnum));
-            add_library(tcx, cnum, RequireStatic, &mut formats);
+            add_library(tcx, cnum, RequireStatic, &mut formats, &mut unavailable_as_static);
             ret[cnum.as_usize() - 1] = Linkage::Static;
         }
     }
@@ -252,6 +254,7 @@ fn add_library(
     cnum: CrateNum,
     link: LinkagePreference,
     m: &mut FxHashMap<CrateNum, LinkagePreference>,
+    unavailable_as_static: &mut Vec<CrateNum>,
 ) {
     match m.get(&cnum) {
         Some(&link2) => {
@@ -263,7 +266,13 @@ fn add_library(
             // This error is probably a little obscure, but I imagine that it
             // can be refined over time.
             if link2 != link || link == RequireStatic {
-                tcx.dcx().emit_err(CrateDepMultiple { crate_name: tcx.crate_name(cnum) });
+                tcx.dcx().emit_err(CrateDepMultiple {
+                    crate_name: tcx.crate_name(cnum),
+                    non_static_deps: unavailable_as_static
+                        .drain(..)
+                        .map(|cnum| NonStaticCrateDep { crate_name: tcx.crate_name(cnum) })
+                        .collect(),
+                });
             }
         }
         None => {
@@ -272,7 +281,7 @@ fn add_library(
     }
 }
 
-fn attempt_static(tcx: TyCtxt<'_>) -> Option<DependencyList> {
+fn attempt_static(tcx: TyCtxt<'_>, unavailable: &mut Vec<CrateNum>) -> Option<DependencyList> {
     let all_crates_available_as_rlib = tcx
         .crates(())
         .iter()
@@ -281,7 +290,11 @@ fn attempt_static(tcx: TyCtxt<'_>) -> Option<DependencyList> {
             if tcx.dep_kind(cnum).macros_only() {
                 return None;
             }
-            Some(tcx.used_crate_source(cnum).rlib.is_some())
+            let is_rlib = tcx.used_crate_source(cnum).rlib.is_some();
+            if !is_rlib {
+                unavailable.push(cnum);
+            }
+            Some(is_rlib)
         })
         .all(|is_rlib| is_rlib);
     if !all_crates_available_as_rlib {

compiler/rustc_metadata/src/errors.rs

@@ -38,6 +38,14 @@ pub struct RustcLibRequired<'a> {
 #[help]
 pub struct CrateDepMultiple {
     pub crate_name: Symbol,
+    #[subdiagnostic]
+    pub non_static_deps: Vec<NonStaticCrateDep>,
+}
+
+#[derive(Subdiagnostic)]
+#[note(metadata_crate_dep_not_static)]
+pub struct NonStaticCrateDep {
+    pub crate_name: Symbol,
 }
 
 #[derive(Diagnostic)]