darwin/driver: Support using SDKROOT to define the default for -isysroot.
- The SDKROOT environment variable is the de facto way to set the default SDK
for a number of tools, join forces with them.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@162116 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp
index 01c6623..5cf97b7 100644
--- a/lib/Driver/ToolChains.cpp
+++ b/lib/Driver/ToolChains.cpp
@@ -442,6 +442,20 @@
void Darwin::AddDeploymentTarget(DerivedArgList &Args) const {
const OptTable &Opts = getDriver().getOpts();
+ // Support allowing the SDKROOT environment variable used by xcrun and other
+ // Xcode tools to define the default sysroot, by making it the default for
+ // isysroot.
+ if (!Args.hasArg(options::OPT_isysroot)) {
+ if (char *env = ::getenv("SDKROOT")) {
+ // We only use this value as the default if it is an absolute path and
+ // exists.
+ if (llvm::sys::path::is_absolute(env) && llvm::sys::fs::exists(env)) {
+ Args.append(Args.MakeSeparateArg(
+ 0, Opts.getOption(options::OPT_isysroot), env));
+ }
+ }
+ }
+
Arg *OSXVersion = Args.getLastArg(options::OPT_mmacosx_version_min_EQ);
Arg *iOSVersion = Args.getLastArg(options::OPT_miphoneos_version_min_EQ);
Arg *iOSSimVersion = Args.getLastArg(