Regression: Cross-compilation from macOS to other platforms fails in libc

[alexrp]

See these logs:

• https://github.com/alexrp/zig-msbuild-sdk/actions/runs/1215768810
• https://github.com/alexrp/zig-msbuild-sdk/actions/runs/1215823335

Some examples:

ZIGCOMPILE : error : unable to build glibc shared objects: FileNotFound [/Users/runner/work/zig-msbuild-sdk/zig-msbuild-sdk/src/samples/cxxexe/cxxexe.cxxproj]

ZIGCOMPILE : error : unable to build glibc CRT file: BuildingLibCObjectFailed [/Users/runner/work/zig-msbuild-sdk/zig-msbuild-sdk/src/samples/cxxexe/cxxexe.cxxproj]

ZIGCOMPILE : error : unable to build mingw-w64 CRT file: BuildingLibCObjectFailed [/Users/runner/work/zig-msbuild-sdk/zig-msbuild-sdk/src/samples/cexe/cexe.cproj]

[andrewrk]

Hi, thank you for the bug report.

Zig 0.8.1

Please verify that the problem still occurs with master branch, and then I will re-open this issue.

[alexrp]

@andrewrk I only just now got around to checking this again. Still happens with 0.9.0.

https://github.com/alexrp/zig-msbuild-sdk/actions/runs/1604452176

ReleaseFast

ZIGCOMPILE : error : unable to build glibc CRT file: BuildingLibCObjectFailed [/Users/runner/work/zig-msbuild-sdk/zig-msbuild-sdk/src/samples/cxxexe/cxxexe.cxxproj]
ZIGCOMPILE : error : unable to build glibc shared objects: FileNotFound [/Users/runner/work/zig-msbuild-sdk/zig-msbuild-sdk/src/samples/cxxexe/cxxexe.cxxproj]
ZIGCOMPILE : error : unable to build mingw-w64 CRT file: BuildingLibCObjectFailed [/Users/runner/work/zig-msbuild-sdk/zig-msbuild-sdk/src/samples/cexe/cexe.cproj]
ZIGCOMPILE : error : unable to build mingw-w64 CRT file: BuildingLibCObjectFailed [/Users/runner/work/zig-msbuild-sdk/zig-msbuild-sdk/src/samples/cexe/cexe.cproj]
ZIGCOMPILE : error : unable to build mingw-w64 CRT file: BuildingLibCObjectFailed [/Users/runner/work/zig-msbuild-sdk/zig-msbuild-sdk/src/samples/cxxexe/cxxexe.cxxproj]

ReleaseSmall

ZIGCOMPILE : error : unable to build glibc CRT file: BuildingLibCObjectFailed [/Users/runner/work/zig-msbuild-sdk/zig-msbuild-sdk/src/samples/cxxexe/cxxexe.cxxproj]
ZIGCOMPILE : error : unable to build glibc shared objects: FileNotFound [/Users/runner/work/zig-msbuild-sdk/zig-msbuild-sdk/src/samples/cxxexe/cxxexe.cxxproj]

[alexrp]

@andrewrk can this be reopened? (My understanding is that 0.9.0 was basically equivalent to master when I tested right after it was released.)

[andrewrk]

Can you suggest how to reproduce this issue? What commands cause those errors to be produced?

[alexrp]

It should be reproducible like this without installing anything .NET-related:

$ git clone git@github.com:alexrp/zig-msbuild-sdk.git
$ cd zig-msbuild-sdk/src/samples/cexe
$ ZIG_LOCAL_CACHE_DIR=obj/Debug/linux-x64/zig-cache zig cc -fdiagnostics-format=msvc -target x86_64-linux.3.10-gnu.2.17 -fPIE -Og -g -std=gnu2x -fexceptions -fno-strict-aliasing -Wanon-enum-enum-conversion -Wassign-enum -Wcompletion-handler -Wconditional-uninitialized -Wdeprecated -Wextra -Wformat-pedantic -Wformat-type-confusion -Wimplicit-fallthrough -Wkeyword-macro -Wloop-analysis -Wover-aligned -Wshadow-all -Wswitch-enum -Wall -Warray-bounds-pointer-arithmetic -Wc++-compat -Wcast-align -Wcast-qual -Wcomma -Wfloat-equal -Wpointer-arith -Wshift-sign-overflow -Walloca -Wnon-gcc -Wsigned-enum-bitfield -Werror=newline-eof -Wconsumed -Wnullable-to-nonnull-conversion -Wthread-safety -Werror=date-time -no-canonical-prefixes -fdebug-compilation-dir . -fno-lto -D ZIG_MAJOR=0 -D ZIG_MINOR=9 -D ZIG_PATCH=0 -D "ZIG_VERSION=\"0.9.0\"" -D ZIG_RID_LINUX_X64 -D ZIG_CPU_X86_64 -D ZIG_BIT_64 -D ZIG_OS_LINUX -D ZIG_ABI_GNU -D ZIG_BO_LITTLE -D ZIG_LIB_GLIBC -D "ZIG_RID=\"linux-x64\"" -D "ZIG_CPU=\"x86_64\"" -D ZIG_BIT=64 -D "ZIG_OS=\"linux\"" -D "ZIG_ABI=\"gnu\"" -D "ZIG_BO=\"little\"" -D "ZIG_LIB=\"glibc\"" -D ZIG_CFG_DEBUG -D "ZIG_CFG=\"Debug\"" -D "ZIG_PKG_AUTHORS=\"cexe\"" -D "ZIG_PKG_COPYRIGHT=\"\"" -D "ZIG_PKG_DESCRIPTION=\"\"" -D "ZIG_PKG_LICENSE=\"\"" -D "ZIG_PKG_NAME=\"cexe\"" -D "ZIG_PKG_PRODUCT=\"cexe\"" -D "ZIG_PKG_REPOSITORY=\"\"" -D "ZIG_PKG_VERSION=\"1.0.0\"" -D "ZIG_PKG_WEBSITE=\"\"" -I . -include prelude.h -Wl,-rpath,'$ORIGIN' main.c -o obj/Debug/linux-x64/cexe -gen-cdb-fragment-path obj/Debug/linux-x64/cdb

(I don't have a macOS machine to test directly on, but the command that gets executed by the SDK should look like the above.)

I'm sure a lot of these flags aren't necessary to reproduce the issue, but without a macOS machine, I can't easily narrow it down. It's worth noting that the sample projects get built in parallel so it's not unthinkable that this might be some sort of cache issue (although as you can see, every build gets a separate ZIG_LOCAL_CACHE_DIR for the configuration/platform combination being targeted, so maybe not).

---

If instead you want to reproduce with .NET 6 installed, as is done on the CI run linked earlier, you can do the following:

$ git clone git@github.com:alexrp/zig-msbuild-sdk.git
$ cd zig-msbuild-sdk
$ dotnet build
$ dotnet build src/samples -c Debug -v:n # or Release

This will build all the samples in parallel for every target triple supported by the SDK, in either Debug or Release mode. The -v:n flag ensures that all zig invocations are logged in full along with their output. (This reminded me that I needed to do that for my CI runs.)

[kubkon]

@alexrp Hi Alex! I've tried reproing your issue locally on my Intel MBP but everything build fine - I used the first 3 commands you listed. One observation though: is it on purpose that your command targets x86_64-linux or should it actually be x86_64-windows instead?

[alexrp]

@kubkon I'm not sure I follow; why x86_64-windows specifically?

If you take a look through the logs posted above (#100, #101, #106, #111), you'll see that there are various cross-compilation issues going from macOS to any other platform (Windows/Linux, x86/x86-64/ARM64...). These didn't show up in 0.8.0.

I've kicked off a few extra builds (with vezel-dev/zig-sdk@3596f4a in place) to hopefully get some more useful logs as the failures seem to be somewhat random: #112, #113, #114

[kubkon]

@alexrp oh, ok, so could you try with latest master instead of 0.9.0? Here's the download link to the latest nightly: https://ziglang.org/builds/zig-macos-x86_64-0.10.0-dev.665+f0400ad93.tar.xz It didn't repro for me locally with latest master and I'm curious if it will be the same for you. Also, while we are here, would you mind explaining how to use dotnet? In paticular, where do I set the path to the zig binary?

[alexrp]

could you try with latest master instead of 0.9.0?

I can try to find some time to set up a repo to test it on GitHub Actions; I don't have a macOS machine, so I'll need to hack together a workflow to do it.

In paticular, where do I set the path to the zig binary?

The toolsets set ZigExePath to tell the SDK where to find zig / zig.exe.

To override that ZigExePath definition from the command line, you would do something like:

$ dotnet build src/samples -c Debug -v:n -p:ZigExePath=/path/to/zig

(You don't need to override the other variables, such as ZigLibPath, as these aren't needed/used by the SDK. They're just there in case users of the toolset packages might need them.)