diff --git a/compiler/rustc_session/src/config.rs b/compiler/rustc_session/src/config.rs index cfeadf3c7595a..ac6eeca300775 100644 --- a/compiler/rustc_session/src/config.rs +++ b/compiler/rustc_session/src/config.rs @@ -16,10 +16,11 @@ use std::{cmp, fmt, fs, iter}; use externs::{ExternOpt, split_extern_opt}; use rustc_data_structures::fx::{FxHashSet, FxIndexMap}; -use rustc_data_structures::stable_hasher::{StableOrd, ToStableHashKey}; +use rustc_data_structures::stable_hasher::{StableHasher, StableOrd, ToStableHashKey}; use rustc_errors::emitter::HumanReadableErrorType; use rustc_errors::{ColorConfig, DiagArgValue, DiagCtxtFlags, IntoDiagArg}; use rustc_feature::UnstableFeatures; +use rustc_hashes::Hash64; use rustc_macros::{Decodable, Encodable, HashStable_Generic}; use rustc_span::edition::{DEFAULT_EDITION, EDITION_NAME_LIST, Edition, LATEST_STABLE_EDITION}; use rustc_span::source_map::FilePathMapping; @@ -1198,7 +1199,25 @@ pub struct OutputFilenames { pub const RLINK_EXT: &str = "rlink"; pub const RUST_CGU_EXT: &str = "rcgu"; pub const DWARF_OBJECT_EXT: &str = "dwo"; +pub const MAX_FILENAME_LENGTH: usize = 143; // ecryptfs limits filenames to 143 bytes see #49914 +/// Ensure the filename is not too long, as some filesystems have a limit. +/// If the filename is too long, hash part of it and append the hash to the filename. +/// This is a workaround for long crate names generating overly long filenames. +fn maybe_strip_file_name(mut path: PathBuf) -> PathBuf { + if path.file_name().map_or(0, |name| name.len()) > MAX_FILENAME_LENGTH { + let filename = path.file_name().unwrap().to_string_lossy(); + let hash_len = 64 / 4; // Hash64 is 64 bits encoded in hex + let stripped_len = filename.len() - MAX_FILENAME_LENGTH + hash_len; + + let mut hasher = StableHasher::new(); + filename[..stripped_len].hash(&mut hasher); + let hash = hasher.finish::(); + + path.set_file_name(format!("{:x}-{}", hash, &filename[stripped_len..])); + } + path +} impl OutputFilenames { pub fn new( out_directory: PathBuf, @@ -1291,7 +1310,7 @@ impl OutputFilenames { } let temps_directory = self.temps_directory.as_ref().unwrap_or(&self.out_directory); - self.with_directory_and_extension(temps_directory, &extension) + maybe_strip_file_name(self.with_directory_and_extension(temps_directory, &extension)) } pub fn temp_path_for_diagnostic(&self, ext: &str) -> PathBuf { diff --git a/tests/run-make/lto-long-filenames/main.rs b/tests/run-make/lto-long-filenames/main.rs new file mode 100644 index 0000000000000..daedff5c05fc1 --- /dev/null +++ b/tests/run-make/lto-long-filenames/main.rs @@ -0,0 +1,7 @@ +// This file has very long lines, but there is no way to avoid it as we are testing +// long crate names. so: +// ignore-tidy-linelength + +extern crate generated_large_large_large_large_large_large_large_large_large_large_large_large_large_large_large_large_large_crate_name; + +fn main() {} diff --git a/tests/run-make/lto-long-filenames/rmake.rs b/tests/run-make/lto-long-filenames/rmake.rs new file mode 100644 index 0000000000000..9e0ba63e9f5b8 --- /dev/null +++ b/tests/run-make/lto-long-filenames/rmake.rs @@ -0,0 +1,32 @@ +// This file has very long lines, but there is no way to avoid it as we are testing +// long crate names. so: +// ignore-tidy-linelength + +// A variant of the smoke test to check that link time optimization +// (LTO) is accepted by the compiler, and that +// passing its various flags still results in successful compilation, even for very long crate names. +// See https://github.com/rust-lang/rust/issues/49914 + +//@ ignore-cross-compile + +use std::fs; + +use run_make_support::{rfs, rustc}; + +// This test make sure we don't get such following error: +// error: could not write output to generated_large_large_large_large_large_large_large_large_large_large_large_large_large_large_large_large_large_crate_name.generated_large_large_large_large_large_large_large_large_large_large_large_large_large_large_large_large_large_crate_name.9384edb61bfd127c-cgu.0.rcgu.o: File name too long +// as reported in issue #49914 +fn main() { + let lto_flags = ["-Clto", "-Clto=yes", "-Clto=off", "-Clto=thin", "-Clto=fat"]; + let aux_file = "generated_large_large_large_large_large_large_large_large_large_large_large_large_large_large_large_large_large_crate_name.rs"; + // The auxiliary file is used to test long crate names. + // The file name is intentionally long to test the handling of long filenames. + // We don't commit it to avoid issues with Windows paths which have known limitations for the full path length. + // Posix usually only have a limit for the length of the file name. + rfs::write(aux_file, "#![crate_type = \"rlib\"]\n"); + + for flag in lto_flags { + rustc().input(aux_file).arg(flag).run(); + rustc().input("main.rs").arg(flag).run(); + } +}