On Feb 2, 2018, at 08:17, Ronald Wampler wrote:

On Thu, Feb 1, 2018 at 3:52 PM, Ryan Schmidt wrote:

...

I'm trying to fix the textmate2 port in MacPorts. It fails to build on OS X 10.10 and earlier, and I think the reason is that the code uses Objective-C lightweight generics, a feature introduced in the 10.11 SDK. So I would like to instruct the build to use the 10.11 SDK, but I can't figure out how to do that. Usually I would set environment variables:

CFLAGS='-isysroot/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk' CPPFLAGS='-isysroot/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk' CXXFLAGS='-isysroot/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk' LDFLAGS='-Wl,-syslibroot,/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk' OBJCFLAGS='-isysroot/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk' OBJCXXFLAGS='-isysroot/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk'

But textmate's configure script isn't an autotools one and it doesn't appear to honor these environment variables. So how can I tell the build system I want to use a different SDK? I see that the configure script explicitly passes CC and CXX to bin/gen_build. Do I need to modify the configure script to also explicitly pass the other environment variables or is there an easier way that doesn't involve modifying the build system?

You can try passing -isysroot via CC and CXX.

CC='xcrun clang -isysroot/path/to/sdk' CXX='xcrun clang++ -isysroot/path/to/sdk' ./configure

I could try that. I thought it was required to use -isysroot at compile time and -Wl,-syslibroot, at link time, hence the need to specify *C*FLAGS and LDFLAGS separately.

https://developer.apple.com/library/content/documentation/DeveloperTools/Con...

On Feb 3, 2018, at 08:58, Ronald Wampler wrote:

On Fri, Feb 2, 2018 at 10:03 PM, Ryan Schmidt wrote:

...

On Feb 2, 2018, at 08:17, Ronald Wampler wrote:

...

You can try passing -isysroot via CC and CXX.

CC='xcrun clang -isysroot/path/to/sdk' CXX='xcrun clang++ -isysroot/path/to/sdk' ./configure

I could try that. I thought it was required to use -isysroot at compile time and -Wl,-syslibroot, at link time, hence the need to specify *C*FLAGS and LDFLAGS separately.

https://developer.apple.com/library/content/documentation/DeveloperTools/Con...

I think the documentation is out of date wrt to clang. On Apple platforms, clang will set -syslibroot to -isysroot and will pass that to the linker. I am not sure when this was supported but you can verify it by running `clang -isysroot /path/to/sdk -### a.o` and check if -syslibroot is set to '/path/to/sdk' and passed to the linker.

Thanks, just using -isysroot works.

If you're not sure whether the LDFLAGS will be passed to the compiler or to the linker, then you have to use -Wl,-syslibroot,. But since for textmate we're sure that we're passing the flag to the compiler, using -isysroot works fine.

There is a build failure when using the Xcode 7.2.1 or earlier version of the OS X 10.11 SDK; here's the fix:

https://github.com/textmate/textmate/pull/1402