Cannot find stdio.h - macos

Question

I am using macOS.
I am trying to build the code of mozilla-central.
While running the command ./mach build, the build fails at the compile step. Here are the relevant stack traces:
stack backtrace:
0:20.24 0: 0x10436b5ff - std::sys::unix::backtrace::tracing::imp::unwind_backtrace::hed04c7a1477ef1e3
0:20.24 1: 0x10434499d - std::sys_common::backtrace::print::h336400f22676933f
0:20.24 2: 0x104373bd3 - std::panicking::default_hook::{{closure}}::h0d6700a02d682978
0:20.24 3: 0x10437395c - std::panicking::default_hook::h90363c6d6ac04260
0:20.24 4: 0x1043742fb - std::panicking::rust_panic_with_hook::h81c4f3add25e6667
0:20.24 5: 0x1043740ce - std::panicking::continue_panic_fmt::hfa057b7c1de88179
0:20.24 6: 0x104374020 - std::panicking::begin_panic_fmt::hd1123702300ea9f2
0:20.24 7: 0x1035f4e6d - build_script_build::build_gecko::bindings::write_binding_file::h2d9a397b93e6a614
0:20.24 8: 0x1035f651c - build_script_build::build_gecko::bindings::generate_bindings::ha066bc11b076e01d
0:20.24 9: 0x1043808fe - __rust_maybe_catch_panic
0:20.24 10: 0x1035eea9f - std::panicking::try::hcbd901ede6e8004c
0:20.32 11: 0x1035e335c - <F as alloc::boxed::FnBox<A>>::call_box::h638a7c5eb8c94414
0:20.33 12: 0x104373037 - std::sys_common::thread::start_thread::h78b1dd404be976ad
0:20.33 13: 0x1043436c8 - std::sys::unix::thread::Thread::new::thread_start::h27c6becca8cf44e0
0:20.33 14: 0x7fff636208cc - _pthread_body
0:20.33 15: 0x7fff6362083e - _pthread_start
0:20.33 /usr/local/Cellar/llvm/6.0.1/include/c++/v1/stdio.h:108:15: fatal error: 'stdio.h' file not found
0:20.33 /usr/local/Cellar/llvm/6.0.1/include/c++/v1/stdio.h:108:15: fatal error: 'stdio.h' file not found, err: true
0:20.37 thread '<unnamed>' panicked at 'Failed to generate bindings
According to me, the root cause is:
/usr/local/Cellar/llvm/6.0.1/include/c++/v1/stdio.h:108:15: fatal error: 'stdio.h' file not found, err: true
The solution listed online was to install xcode command line tools using:
xcode-select --install
I have already done this.

Answer 1

Try setting SDKROOT explicitly to the system SDK:
export SDKROOT=$(xcrun --sdk macosx --show-sdk-path)
Doing it avoids the need for creating symlinks in /usr.
This error seem recurrent, for example, if you installed another compiler (e.g. gcc from brew). Setting SDKROOT became so common that it might be a good idea to add it to ~/.bash_profile.

Answer 2

The root reason is due to a missing /usr/include directory.
Installing command-line tools (xcode-select --install), sometimes, will not automatically add it.
The Link shows the correct way:
After installing command-line tools
Install the package at:
# run this in Terminal
open /Library/Developer/CommandLineTools/Packages/macOS_SDK_headers_for_macOS_10.14.pkg
After that,
you should have a directory /usr/include with header files

Answer 3

I had the same problem for compiling R packages, and running xcode-select --install and macOS_SDK_headers_for_macOS_10.14.pkg did not solve the problem.
I discovered that there seems to be some confusion from Apples side between macOS 10.14 and 10.15, since I'm running Mojave (10.14) with the latest xcode 11.0 (11A420a), and when clang compiles it looks for the MacOSX10.14.sdk sysroot directory in
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/
but there only MacOSX10.15.sdk is present (along with other stuff). I fixed this with
pushd /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/
sudo ln -s MacOSX.sdk MacOSX10.14.sdk
popd
Now I can install packages in RStudio again.

Answer 4

This is a comment to Rick Li. It’s too long to fit into comment area.
The solution provided by Rick Li isn’t necessary the correct way. It’s only the easiest way. According to Xcode 10 release note:
…If you are the maintainer of such software, we encourage you to update your project to work with the SDK or file a bug report for issues that are preventing you from doing so. As a workaround, an extra package is provided which will install the headers to the base system. In a future release, this package will no longer be provided. …
So the right way is to contact Mozilla team that their application won’t build without hack. It will break eventually.
If you don’t take this seriously, it would bite you in future. I still recall that Apple deprecated 32-bit application on macOS 10.13 (High Sierra). Now they formally disabled it in macOS 10.15 (Catalina) and I hear about people crying everywhere. Be responsible of your choice.

Answer 5

I had the same problem. Tried to install the command-line tools via xcode-select --install but it didn't worked out for me.
After more research i found out that you can download the command-line tools on Apples official developer support site (Link)
Search for command and download first suggestion.
Run the .dmg file and see if works.
Worked out great for me!

Answer 6

I had the same problem (suddenly) compiling my own project - not finding <stdio.h> and <wchar.h>.
Running xcode-select --install said
xcode-select: error: command line tools are already installed, use "Software Update" to install updates
The following steps worked for me:
Open Xcode once and allow it installing necessary components
Remove the CMake cache files and retry cmake and build
I'm on macOS Big Sur 11.2.3 with Xcode version 12.5.

Answer 7

Add -isysroot with needed MaсOSX version
It work for me: MacOS Big Sure 11.4 & XCode 12.5.1
Know latest MacOS SDK version path by command:
xcrun --sdk macosx --show-sdk-path
Add path result to -isysroot:
-isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX11.3.sdk
UPD: if solution above did not help, try put -I to include from MacOS SDK
-I$(MACOSSDK)/usr/include\
-I$(MACOSSDK)/usr/include/c++\
-I$(MACOSSDK)/usr/include/c++/v1\
-I$(MACOSSDK)/usr/include/c++/v1/ext\
-Wnonportable-include-path

Answer 8

Command Line Tools Path Setting
I saw that "Command Line Tools" is not set in the xcode settings, as shown in the figure, click to select the Xcode path, and then compile, there is no such error.