Auto merge of rust-lang#138693 - matthiaskrgr:rollup-ejq8mwp, r=matthiaskrgr

Rollup of 10 pull requests

Successful merges:

 - rust-lang#136177 (clarify BufRead::{fill_buf, consume} docs)
 - rust-lang#138654 (Remove the regex dependency from coretests)
 - rust-lang#138655 (rustc-dev-guide sync)
 - rust-lang#138656 (Remove double nesting in post-merge workflow)
 - rust-lang#138658 (CI: mirror alpine and centos images to ghcr)
 - rust-lang#138659 (coverage: Don't store a body span in `FunctionCoverageInfo`)
 - rust-lang#138661 (Revert: Add *_value methods to proc_macro lib)
 - rust-lang#138670 (Remove existing AFIDT implementation)
 - rust-lang#138674 (Various codegen_llvm cleanups)
 - rust-lang#138684 (use then in docs for `fuse` to enhance readability)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

Diff for: .github/workflows/ghcr.yml

@@ -5,6 +5,9 @@
 # Docker Hub has a rate limit, while ghcr.io doesn't.
 # Those images are pushed to ghcr.io by this job.
 #
+# While Docker Hub rate limit *shouldn't* be an issue on GitHub Actions,
+# it certainly is for AWS codebuild.
+#
 # Note that authenticating to DockerHub or other registries isn't possible
 # for PR jobs, because forks can't access secrets.
 # That's why we use ghcr.io: it has no rate limit and it doesn't require authentication.
@@ -54,6 +57,10 @@ jobs:
             "ubuntu:22.04"
             # Mirrored because used by all linux CI jobs, including mingw-check-tidy
             "moby/buildkit:buildx-stable-1"
+            # Mirrored because used when CI is running inside a Docker container
+            "alpine:3.4"
+            # Mirrored because used by dist-x86_64-linux
+            "centos:7"
           )
 
           # Mirror each image from DockerHub to ghcr.io

Diff for: .github/workflows/post-merge.yml

@@ -35,13 +35,12 @@ jobs:
 
           cd src/ci/citool
 
-          printf "*This is an experimental post-merge analysis report. You can ignore it.*\n\n" > output.log
-          printf "<details>\n<summary>Post-merge report</summary>\n\n" >> output.log
+          printf "<details>\n<summary>What is this?</summary>\n" >> output.log
+          printf "This is an experimental post-merge analysis report that shows differences in test outcomes between the merged PR and its parent PR.\n" >> output.log
+          printf "</details>\n\n" >> output.log
 
           cargo run --release post-merge-report ${PARENT_COMMIT} ${{ github.sha }} >> output.log
 
-          printf "</details>\n" >> output.log
-
           cat output.log
 
           gh pr comment ${HEAD_PR} -F output.log

Diff for: Cargo.lock

@@ -2082,13 +2082,6 @@ version = "0.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4ee93343901ab17bd981295f2cf0026d4ad018c7c31ba84549a4ddbb47a45104"
 
-[[package]]
-name = "literal-escaper"
-version = "0.0.0"
-dependencies = [
- "rustc-std-workspace-std 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "lld-wrapper"
 version = "0.1.0"
@@ -3155,12 +3148,6 @@ version = "1.0.1"
 name = "rustc-std-workspace-std"
 version = "1.0.1"
 
-[[package]]
-name = "rustc-std-workspace-std"
-version = "1.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "aba676a20abe46e5b0f1b0deae474aaaf31407e6c71147159890574599da04ef"
-
 [[package]]
 name = "rustc_abi"
 version = "0.0.0"
@@ -3199,7 +3186,6 @@ name = "rustc_ast"
 version = "0.0.0"
 dependencies = [
  "bitflags",
- "literal-escaper",
  "memchr",
  "rustc_ast_ir",
  "rustc_data_structures",
@@ -3909,7 +3895,6 @@ name = "rustc_lexer"
 version = "0.0.0"
 dependencies = [
  "expect-test",
- "literal-escaper",
  "memchr",
  "unicode-properties",
  "unicode-xid",
@@ -4172,7 +4157,6 @@ name = "rustc_parse"
 version = "0.0.0"
 dependencies = [
  "bitflags",
- "literal-escaper",
  "rustc_ast",
  "rustc_ast_pretty",
  "rustc_data_structures",
@@ -4195,7 +4179,6 @@ dependencies = [
 name = "rustc_parse_format"
 version = "0.0.0"
 dependencies = [
- "literal-escaper",
  "rustc_index",
  "rustc_lexer",
 ]

Diff for: compiler/rustc_ast/Cargo.toml

@@ -6,7 +6,6 @@ edition = "2024"
 [dependencies]
 # tidy-alphabetical-start
 bitflags = "2.4.1"
-literal-escaper = { path = "../../library/literal-escaper" }
 memchr = "2.7.4"
 rustc_ast_ir = { path = "../rustc_ast_ir" }
 rustc_data_structures = { path = "../rustc_data_structures" }

Diff for: compiler/rustc_ast/src/util/literal.rs

@@ -2,7 +2,7 @@
 
 use std::{ascii, fmt, str};
 
-use literal_escaper::{
+use rustc_lexer::unescape::{
     MixedUnit, Mode, byte_from_char, unescape_byte, unescape_char, unescape_mixed, unescape_unicode,
 };
 use rustc_span::{Span, Symbol, kw, sym};

Diff for: compiler/rustc_codegen_llvm/src/coverageinfo/mapgen/covfun.rs

@@ -105,9 +105,14 @@ fn fill_region_tables<'tcx>(
     ids_info: &'tcx CoverageIdsInfo,
     covfun: &mut CovfunRecord<'tcx>,
 ) {
-    // Currently a function's mappings must all be in the same file as its body span.
+    // Currently a function's mappings must all be in the same file, so use the
+    // first mapping's span to determine the file.
     let source_map = tcx.sess.source_map();
-    let source_file = source_map.lookup_source_file(fn_cov_info.body_span.lo());
+    let Some(first_span) = (try { fn_cov_info.mappings.first()?.span }) else {
+        debug_assert!(false, "function has no mappings: {:?}", covfun.mangled_function_name);
+        return;
+    };
+    let source_file = source_map.lookup_source_file(first_span.lo());
 
     // Look up the global file ID for that file.
     let global_file_id = global_file_table.global_file_id_for_file(&source_file);
@@ -118,9 +123,8 @@ fn fill_region_tables<'tcx>(
     let ffi::Regions { code_regions, branch_regions, mcdc_branch_regions, mcdc_decision_regions } =
         &mut covfun.regions;
 
-    let make_cov_span = |span: Span| {
-        spans::make_coverage_span(local_file_id, source_map, fn_cov_info, &source_file, span)
-    };
+    let make_cov_span =
+        |span: Span| spans::make_coverage_span(local_file_id, source_map, &source_file, span);
     let discard_all = tcx.sess.coverage_discard_all_spans_in_codegen();
 
     // For each counter/region pair in this function+file, convert it to a

Diff for: compiler/rustc_codegen_llvm/src/coverageinfo/mapgen/spans.rs

@@ -1,4 +1,3 @@
-use rustc_middle::mir::coverage::FunctionCoverageInfo;
 use rustc_span::source_map::SourceMap;
 use rustc_span::{BytePos, Pos, SourceFile, Span};
 use tracing::debug;
@@ -19,11 +18,10 @@ use crate::coverageinfo::mapgen::LocalFileId;
 pub(crate) fn make_coverage_span(
     file_id: LocalFileId,
     source_map: &SourceMap,
-    fn_cov_info: &FunctionCoverageInfo,
     file: &SourceFile,
     span: Span,
 ) -> Option<ffi::CoverageSpan> {
-    let span = ensure_non_empty_span(source_map, fn_cov_info, span)?;
+    let span = ensure_non_empty_span(source_map, span)?;
 
     let lo = span.lo();
     let hi = span.hi();
@@ -55,36 +53,22 @@ pub(crate) fn make_coverage_span(
     })
 }
 
-fn ensure_non_empty_span(
-    source_map: &SourceMap,
-    fn_cov_info: &FunctionCoverageInfo,
-    span: Span,
-) -> Option<Span> {
+fn ensure_non_empty_span(source_map: &SourceMap, span: Span) -> Option<Span> {
     if !span.is_empty() {
         return Some(span);
     }
 
-    let lo = span.lo();
-    let hi = span.hi();
-
-    // The span is empty, so try to expand it to cover an adjacent '{' or '}',
-    // but only within the bounds of the body span.
-    let try_next = hi < fn_cov_info.body_span.hi();
-    let try_prev = fn_cov_info.body_span.lo() < lo;
-    if !(try_next || try_prev) {
-        return None;
-    }
-
+    // The span is empty, so try to enlarge it to cover an adjacent '{' or '}'.
     source_map
         .span_to_source(span, |src, start, end| try {
             // Adjusting span endpoints by `BytePos(1)` is normally a bug,
             // but in this case we have specifically checked that the character
             // we're skipping over is one of two specific ASCII characters, so
             // adjusting by exactly 1 byte is correct.
-            if try_next && src.as_bytes()[end] == b'{' {
-                Some(span.with_hi(hi + BytePos(1)))
-            } else if try_prev && src.as_bytes()[start - 1] == b'}' {
-                Some(span.with_lo(lo - BytePos(1)))
+            if src.as_bytes().get(end).copied() == Some(b'{') {
+                Some(span.with_hi(span.hi() + BytePos(1)))
+            } else if start > 0 && src.as_bytes()[start - 1] == b'}' {
+                Some(span.with_lo(span.lo() - BytePos(1)))
             } else {
                 None
             }