Add c_std and cpp_std properties.

Test: Checked showcommands ouput for each setting.
Bug: None
Change-Id: Ibe02352f19ca2777b9a419136270e5c4390f1149

3 files changed, 28 insertions, 3 deletions

diff --git a/cc/compiler.go b/cc/compiler.go
index d53e799a..e962949b 100644
--- a/cc/compiler.go
+++ b/cc/compiler.go
@@ -86,6 +86,16 @@ type BaseCompilerProperties struct {
 	// pass -frtti instead of -fno-rtti
 	Rtti *bool
 
+	// C standard version to use. Can be a specific version (such as "gnu11"),
+	// "experimental" (which will use draft versions like C1x when available),
+	// or the empty string (which will use the default).
+	C_std string
+
+	// C++ standard version to use. Can be a specific version (such as
+	// "gnu++11"), "experimental" (which will use draft versions like C++1z when
+	// available), or the empty string (which will use the default).
+	Cpp_std string
+
 	// if set to false, use -std=c++* instead of -std=gnu++*
 	Gnu_extensions *bool
 
@@ -307,7 +317,18 @@ func (compiler *baseCompiler) compilerFlags(ctx ModuleContext, flags Flags) Flag
 
 	if !ctx.sdk() {
 		cStd := config.CStdVersion
+		if compiler.Properties.C_std == "experimental" {
+			cStd = config.ExperimentalCStdVersion
+		} else if compiler.Properties.C_std != "" {
+			cStd = compiler.Properties.C_std
+		}
+
 		cppStd := config.CppStdVersion
+		if compiler.Properties.Cpp_std == "experimental" {
+			cppStd = config.ExperimentalCppStdVersion
+		} else if compiler.Properties.Cpp_std != "" {
+			cppStd = compiler.Properties.Cpp_std
+		}
 
 		if !flags.Clang {
 			// GCC uses an invalid C++14 ABI (emits calls to
diff --git a/cc/config/global.go b/cc/config/global.go
index e248040d..e254a1c8 100644
--- a/cc/config/global.go
+++ b/cc/config/global.go
@@ -65,9 +65,11 @@ var (
 		"-w",
 	}
 
-	CStdVersion      = "gnu99"
-	CppStdVersion    = "gnu++14"
-	GccCppStdVersion = "gnu++11"
+	CStdVersion               = "gnu99"
+	CppStdVersion             = "gnu++14"
+	GccCppStdVersion          = "gnu++11"
+	ExperimentalCStdVersion   = "gnu11"
+	ExperimentalCppStdVersion = "gnu++1z"
 )
 
 var pctx = android.NewPackageContext("android/soong/cc/config")
diff --git a/cc/makevars.go b/cc/makevars.go
index 2e64e3c2..30d83e8e 100644
--- a/cc/makevars.go
+++ b/cc/makevars.go
@@ -60,6 +60,8 @@ func makeVarsProvider(ctx android.MakeVarsContext) {
 	ctx.Strict("DEFAULT_C_STD_VERSION", config.CStdVersion)
 	ctx.Strict("DEFAULT_CPP_STD_VERSION", config.CppStdVersion)
 	ctx.Strict("DEFAULT_GCC_CPP_STD_VERSION", config.GccCppStdVersion)
+	ctx.Strict("EXPERIMENTAL_C_STD_VERSION", config.ExperimentalCStdVersion)
+	ctx.Strict("EXPERIMENTAL_CPP_STD_VERSION", config.ExperimentalCppStdVersion)
 
 	ctx.Strict("DEFAULT_GLOBAL_TIDY_CHECKS", "${config.TidyDefaultGlobalChecks}")
 	ctx.Strict("DEFAULT_LOCAL_TIDY_CHECKS", joinLocalTidyChecks(config.DefaultLocalTidyChecks))