From 1ae1461fbf59db8db5dd2fe11bbe22c6adeb1aed Mon Sep 17 00:00:00 2001 From: Alex Crichton Date: Wed, 30 Jul 2014 07:44:20 -0700 Subject: [PATCH] rustc: Link entire archives of native libraries As discovered in #15460, a particular #[link(kind = "static", ...)] line is not actually guaranteed to link the library at all. The reason for this is that if the external library doesn't have any referenced symbols in the object generated by rustc, the entire library is dropped by the linker. For dynamic native libraries, this is solved by passing -lfoo for all downstream compilations unconditionally. For static libraries in rlibs this is solved because the entire archive is bundled in the rlib. The only situation in which this was a problem was when a static native library was linked to a rust dynamic library. This commit brings the behavior of dylibs in line with rlibs by passing the --whole-archive flag to the linker when linking native libraries. On OSX, this uses the -force_load flag. This flag ensures that the entire archive is considered candidate for being linked into the final dynamic library. This is a breaking change because if any static library is included twice in the same compilation unit then the linker will start emitting errors about duplicate definitions now. The fix for this would involve only statically linking to a library once. Closes #15460 [breaking-change] --- src/liballoc/heap.rs | 3 + src/librustc/back/link.rs | 69 ++++++++++++++----- src/librustc_back/archive.rs | 51 +++++++------- src/librustrt/unwind.rs | 3 + src/libstd/rt/backtrace.rs | 3 + src/libstd/rtdeps.rs | 1 + .../run-make/extern-fn-with-union/test.rs | 1 - src/test/run-make/issue-15460/Makefile | 6 ++ src/test/run-make/issue-15460/bar.rs | 14 ++++ src/test/run-make/issue-15460/foo.c | 1 + src/test/run-make/issue-15460/foo.rs | 16 +++++ src/test/run-make/no-duplicate-libs/Makefile | 5 +- src/test/run-make/no-duplicate-libs/bar.rs | 21 ++++++ src/test/run-make/no-duplicate-libs/foo.rs | 21 ++++++ src/test/run-pass/foreign-dupe.rs | 1 - 15 files changed, 170 insertions(+), 46 deletions(-) create mode 100644 src/test/run-make/issue-15460/Makefile create mode 100644 src/test/run-make/issue-15460/bar.rs create mode 100644 src/test/run-make/issue-15460/foo.c create mode 100644 src/test/run-make/issue-15460/foo.rs create mode 100644 src/test/run-make/no-duplicate-libs/bar.rs create mode 100644 src/test/run-make/no-duplicate-libs/foo.rs diff --git a/src/liballoc/heap.rs b/src/liballoc/heap.rs index dc8280e9b836..3175c516d8ef 100644 --- a/src/liballoc/heap.rs +++ b/src/liballoc/heap.rs @@ -136,6 +136,9 @@ mod imp { use libc::{c_char, c_int, c_void, size_t}; #[link(name = "jemalloc", kind = "static")] + #[cfg(not(test))] + extern {} + extern { fn je_mallocx(size: size_t, flags: c_int) -> *mut c_void; fn je_rallocx(ptr: *mut c_void, size: size_t, diff --git a/src/librustc/back/link.rs b/src/librustc/back/link.rs index 090976541496..6c605fc26286 100644 --- a/src/librustc/back/link.rs +++ b/src/librustc/back/link.rs @@ -9,6 +9,7 @@ // except according to those terms. use super::archive::{Archive, ArchiveBuilder, ArchiveConfig, METADATA_FILENAME}; +use super::archive; use super::rpath; use super::rpath::RPathConfig; use super::svh::Svh; @@ -1597,28 +1598,60 @@ fn add_local_native_libraries(cmd: &mut Command, sess: &Session) { // For those that support this, we ensure we pass the option if the library // was flagged "static" (most defaults are dynamic) to ensure that if // libfoo.a and libfoo.so both exist that the right one is chosen. - let takes_hints = sess.targ_cfg.os != abi::OsMacos && sess.targ_cfg.os != abi::OsiOS; + let takes_hints = sess.targ_cfg.os != abi::OsMacos && + sess.targ_cfg.os != abi::OsiOS; - for &(ref l, kind) in sess.cstore.get_used_libraries().borrow().iter() { - match kind { - cstore::NativeUnknown | cstore::NativeStatic => { - if takes_hints { - if kind == cstore::NativeStatic { - cmd.arg("-Wl,-Bstatic"); - } else { - cmd.arg("-Wl,-Bdynamic"); - } - } - cmd.arg(format!("-l{}", *l)); - } - cstore::NativeFramework => { - cmd.arg("-framework"); - cmd.arg(l.as_slice()); - } + let libs = sess.cstore.get_used_libraries(); + let libs = libs.borrow(); + + let mut staticlibs = libs.iter().filter_map(|&(ref l, kind)| { + if kind == cstore::NativeStatic {Some(l)} else {None} + }); + let mut others = libs.iter().filter(|&&(_, kind)| { + kind != cstore::NativeStatic + }); + + // Platforms that take hints generally also support the --whole-archive + // flag. We need to pass this flag when linking static native libraries to + // ensure the entire library is included. + // + // For more details see #15460, but the gist is that the linker will strip + // away any unused objects in the archive if we don't otherwise explicitly + // reference them. This can occur for libraries which are just providing + // bindings, libraries with generic functions, etc. + if takes_hints { + cmd.arg("-Wl,--whole-archive").arg("-Wl,-Bstatic"); + } + let search_path = archive_search_paths(sess); + for l in staticlibs { + if takes_hints { + cmd.arg(format!("-l{}", l)); + } else { + // -force_load is the OSX equivalent of --whole-archive, but it + // involves passing the full path to the library to link. + let lib = archive::find_library(l.as_slice(), + sess.targ_cfg.os, + search_path.as_slice(), + &sess.diagnostic().handler); + let mut v = b"-Wl,-force_load,".to_vec(); + v.push_all(lib.as_vec()); + cmd.arg(v.as_slice()); } } if takes_hints { - cmd.arg("-Wl,-Bdynamic"); + cmd.arg("-Wl,--no-whole-archive").arg("-Wl,-Bdynamic"); + } + + for &(ref l, kind) in others { + match kind { + cstore::NativeUnknown => { + cmd.arg(format!("-l{}", l)); + } + cstore::NativeFramework => { + cmd.arg("-framework").arg(l.as_slice()); + } + cstore::NativeStatic => unreachable!(), + } } } diff --git a/src/librustc_back/archive.rs b/src/librustc_back/archive.rs index e2cadf817d5e..85e0f2f10d8d 100644 --- a/src/librustc_back/archive.rs +++ b/src/librustc_back/archive.rs @@ -95,6 +95,30 @@ fn run_ar(handler: &ErrorHandler, maybe_ar_prog: &Option, } } +pub fn find_library(name: &str, os: abi::Os, search_paths: &[Path], + handler: &ErrorHandler) -> Path { + let (osprefix, osext) = match os { + abi::OsWin32 => ("", "lib"), _ => ("lib", "a"), + }; + // On Windows, static libraries sometimes show up as libfoo.a and other + // times show up as foo.lib + let oslibname = format!("{}{}.{}", osprefix, name, osext); + let unixlibname = format!("lib{}.a", name); + + for path in search_paths.iter() { + debug!("looking for {} inside {}", name, path.display()); + let test = path.join(oslibname.as_slice()); + if test.exists() { return test } + if oslibname != unixlibname { + let test = path.join(unixlibname.as_slice()); + if test.exists() { return test } + } + } + handler.fatal(format!("could not find native static library `{}`, \ + perhaps an -L flag is missing?", + name).as_slice()); +} + impl<'a> Archive<'a> { fn new(config: ArchiveConfig<'a>) -> Archive<'a> { let ArchiveConfig { handler, dst, lib_search_paths, os, maybe_ar_prog } = config; @@ -153,7 +177,9 @@ impl<'a> ArchiveBuilder<'a> { /// Adds all of the contents of a native library to this archive. This will /// search in the relevant locations for a library named `name`. pub fn add_native_library(&mut self, name: &str) -> io::IoResult<()> { - let location = self.find_library(name); + let location = find_library(name, self.archive.os, + self.archive.lib_search_paths.as_slice(), + self.archive.handler); self.add_archive(&location, name, []) } @@ -285,28 +311,5 @@ impl<'a> ArchiveBuilder<'a> { } Ok(()) } - - fn find_library(&self, name: &str) -> Path { - let (osprefix, osext) = match self.archive.os { - abi::OsWin32 => ("", "lib"), _ => ("lib", "a"), - }; - // On Windows, static libraries sometimes show up as libfoo.a and other - // times show up as foo.lib - let oslibname = format!("{}{}.{}", osprefix, name, osext); - let unixlibname = format!("lib{}.a", name); - - for path in self.archive.lib_search_paths.iter() { - debug!("looking for {} inside {}", name, path.display()); - let test = path.join(oslibname.as_slice()); - if test.exists() { return test } - if oslibname != unixlibname { - let test = path.join(unixlibname.as_slice()); - if test.exists() { return test } - } - } - self.archive.handler.fatal(format!("could not find native static library `{}`, \ - perhaps an -L flag is missing?", - name).as_slice()); - } } diff --git a/src/librustrt/unwind.rs b/src/librustrt/unwind.rs index 344d3a0f103d..52b02479f7fc 100644 --- a/src/librustrt/unwind.rs +++ b/src/librustrt/unwind.rs @@ -159,6 +159,9 @@ pub unsafe fn try(f: ||) -> ::core::result::Result<(), Box> { } #[link(name = "rustrt_native", kind = "static")] + #[cfg(not(test))] + extern {} + extern { // Rust's try-catch // When f(...) returns normally, the return value is null. diff --git a/src/libstd/rt/backtrace.rs b/src/libstd/rt/backtrace.rs index 80493ebb4a93..c003e08740de 100644 --- a/src/libstd/rt/backtrace.rs +++ b/src/libstd/rt/backtrace.rs @@ -415,6 +415,9 @@ mod imp { errnum: libc::c_int); enum backtrace_state {} #[link(name = "backtrace", kind = "static")] + #[cfg(not(test))] + extern {} + extern { fn backtrace_create_state(filename: *const libc::c_char, threaded: libc::c_int, diff --git a/src/libstd/rtdeps.rs b/src/libstd/rtdeps.rs index 1717aeb84300..4267d6020b24 100644 --- a/src/libstd/rtdeps.rs +++ b/src/libstd/rtdeps.rs @@ -15,6 +15,7 @@ #![experimental] // All platforms need to link to rustrt +#[cfg(not(test))] #[link(name = "rust_builtin", kind = "static")] extern {} diff --git a/src/test/run-make/extern-fn-with-union/test.rs b/src/test/run-make/extern-fn-with-union/test.rs index 81fe9085af74..f9277ba11f47 100644 --- a/src/test/run-make/extern-fn-with-union/test.rs +++ b/src/test/run-make/extern-fn-with-union/test.rs @@ -12,7 +12,6 @@ extern crate testcrate; use std::mem; -#[link(name = "test", kind = "static")] extern { fn give_back(tu: testcrate::TestUnion) -> u64; } diff --git a/src/test/run-make/issue-15460/Makefile b/src/test/run-make/issue-15460/Makefile new file mode 100644 index 000000000000..e6dd5c4c1af5 --- /dev/null +++ b/src/test/run-make/issue-15460/Makefile @@ -0,0 +1,6 @@ +-include ../tools.mk + +all: $(TMPDIR)/libfoo.a + $(RUSTC) foo.rs -C extra-filename=-383hf8 + $(RUSTC) bar.rs + $(call RUN,bar) diff --git a/src/test/run-make/issue-15460/bar.rs b/src/test/run-make/issue-15460/bar.rs new file mode 100644 index 000000000000..46777f7fbd24 --- /dev/null +++ b/src/test/run-make/issue-15460/bar.rs @@ -0,0 +1,14 @@ +// Copyright 2014 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +extern crate foo; +fn main() { + unsafe { foo::foo() } +} diff --git a/src/test/run-make/issue-15460/foo.c b/src/test/run-make/issue-15460/foo.c new file mode 100644 index 000000000000..85e6cd8c3909 --- /dev/null +++ b/src/test/run-make/issue-15460/foo.c @@ -0,0 +1 @@ +void foo() {} diff --git a/src/test/run-make/issue-15460/foo.rs b/src/test/run-make/issue-15460/foo.rs new file mode 100644 index 000000000000..6917fa555798 --- /dev/null +++ b/src/test/run-make/issue-15460/foo.rs @@ -0,0 +1,16 @@ +// Copyright 2014 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +#![crate_type = "dylib"] + +#[link(name = "foo", kind = "static")] +extern { + pub fn foo(); +} diff --git a/src/test/run-make/no-duplicate-libs/Makefile b/src/test/run-make/no-duplicate-libs/Makefile index 1417da3de36f..fdb6048dc4d5 100644 --- a/src/test/run-make/no-duplicate-libs/Makefile +++ b/src/test/run-make/no-duplicate-libs/Makefile @@ -1,6 +1,7 @@ -include ../tools.mk -all: $(call STATICLIB,foo) $(call STATICLIB,bar) +all: + $(RUSTC) foo.rs + $(RUSTC) bar.rs $(RUSTC) main.rs $(call RUN,main) - diff --git a/src/test/run-make/no-duplicate-libs/bar.rs b/src/test/run-make/no-duplicate-libs/bar.rs new file mode 100644 index 000000000000..8b87b5f0f9a1 --- /dev/null +++ b/src/test/run-make/no-duplicate-libs/bar.rs @@ -0,0 +1,21 @@ +// Copyright 2014 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +#![no_std] +#![feature(lang_items)] +#![crate_type = "dylib"] + +extern crate libc; + +#[no_mangle] +pub extern fn bar() {} + +#[lang = "stack_exhausted"] fn stack_exhausted() {} +#[lang = "eh_personality"] fn eh_personality() {} diff --git a/src/test/run-make/no-duplicate-libs/foo.rs b/src/test/run-make/no-duplicate-libs/foo.rs new file mode 100644 index 000000000000..6f9537c1f449 --- /dev/null +++ b/src/test/run-make/no-duplicate-libs/foo.rs @@ -0,0 +1,21 @@ +// Copyright 2014 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +#![no_std] +#![feature(lang_items)] +#![crate_type = "dylib"] + +extern crate libc; + +#[no_mangle] +pub extern fn foo() {} + +#[lang = "stack_exhausted"] fn stack_exhausted() {} +#[lang = "eh_personality"] fn eh_personality() {} diff --git a/src/test/run-pass/foreign-dupe.rs b/src/test/run-pass/foreign-dupe.rs index 74c1132625f7..577efbd39e14 100644 --- a/src/test/run-pass/foreign-dupe.rs +++ b/src/test/run-pass/foreign-dupe.rs @@ -22,7 +22,6 @@ mod rustrt1 { mod rustrt2 { extern crate libc; - #[link(name = "rust_test_helpers")] extern { pub fn rust_get_test_int() -> libc::intptr_t; }