Use `clang` rather than `clang++` as the linker driver. This ensures
that we do not force a C++ runtime on the general code. This is fine
for now as C++ interop is not yet available for Swift. This prevents
the accidental mix-and-match of various C++ runtimes. This can cause
problems on platforms like android where `libstdc++` is an unsupported
runtime but is generally the default for Linux platforms.
This option tells the compiler where to find a profdata file. The
information in this file enables PGO. For more information about the PGO
infrastructure, look for the -profile-generate option and for the
llvm-profdata tool [1].
[1] http://llvm.org/docs/CommandGuide/llvm-profdata.html
(1) We no longer put the Clang version string in our copy of or symlink to
Clang's resource directory.
(2) Newer Clang builds now generate a separate library for the Apple OS
simulators, instead of a fat binary.
We still need a proper end-to-end test for this, but that depends on
building compiler-rt with Swift, which isn't a standard config yet.
- Add frontend and standard library build support for tvOS.
- Add frontend support for watchOS.
watchOS standard library builds are still disabled during SDK bring-up.
To build for TVOS, specify --tvos to build-script.
To build for watchOS, specify --watchos to build-script (not yet supported).
This patch does not include turning on full tests for TVOS or watchOS, and
will be included in a follow-up patch.
Swift SVN r26278
This adds the -profile-generate flag, which enables LLVM's
instrumentation based profiling. It implements the instrumentation
for basic control flow, such as if statements, loops, and closures.
Swift SVN r25155
