[Modules] Turn on system header validation for implicit modules

After r300027 implicit builds might fail when updating the SDK on
darwin. Make validation of system headers default when implicit modules
is on and allow modules to be rebuild when system headers change.

rdar://problem/19767523

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@330240 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/Driver/Options.td b/include/clang/Driver/Options.td
index 55e87287585fba5dfe13907862e1a64879c4fe12..d8e784a8abb8825791e2798c7c61f69a05dfe78e 100644 (file)
--- a/include/clang/Driver/Options.td
+++ b/include/clang/Driver/Options.td
@@ -1217,6 +1217,8 @@ def fmodules_disable_diagnostic_validation : Flag<["-"], "fmodules-disable-diagn
 def fmodules_validate_system_headers : Flag<["-"], "fmodules-validate-system-headers">,
   Group<i_Group>, Flags<[CC1Option]>,
   HelpText<"Validate the system headers that a module depends on when loading the module">;
+def fno_modules_validate_system_headers : Flag<["-"], "fno-modules-validate-system-headers">,
+  Group<i_Group>, Flags<[DriverOption]>;
 def fmodules : Flag <["-"], "fmodules">, Group<f_Group>,
   Flags<[DriverOption, CC1Option]>,
   HelpText<"Enable the 'modules' language feature">;

diff --git a/lib/Driver/ToolChains/Clang.cpp b/lib/Driver/ToolChains/Clang.cpp
index 6de4f6ea620d8ff9a4f42ecb356a9af1d38bbc82..15e7cf2847c697dbf84c2f23e20ad857daa691e5 100644 (file)
--- a/lib/Driver/ToolChains/Clang.cpp
+++ b/lib/Driver/ToolChains/Clang.cpp
@@ -2546,11 +2546,13 @@ static void RenderModulesOptions(Compilation &C, const Driver &D,
     CmdArgs.push_back("-fmodules-strict-decluse");
 
   // -fno-implicit-modules turns off implicitly compiling modules on demand.
+  bool ImplicitModules = false;
   if (!Args.hasFlag(options::OPT_fimplicit_modules,
                     options::OPT_fno_implicit_modules, HaveClangModules)) {
     if (HaveModules)
       CmdArgs.push_back("-fno-implicit-modules");
   } else if (HaveModules) {
+    ImplicitModules = true;
     // -fmodule-cache-path specifies where our implicitly-built module files
     // should be written.
     SmallString<128> Path;
@@ -2657,7 +2659,11 @@ static void RenderModulesOptions(Compilation &C, const Driver &D,
                     options::OPT_fmodules_validate_once_per_build_session);
   }
 
-  Args.AddLastArg(CmdArgs, options::OPT_fmodules_validate_system_headers);
+  if (Args.hasFlag(options::OPT_fmodules_validate_system_headers,
+                   options::OPT_fno_modules_validate_system_headers,
+                   ImplicitModules))
+    CmdArgs.push_back("-fmodules-validate-system-headers");
+
   Args.AddLastArg(CmdArgs, options::OPT_fmodules_disable_diagnostic_validation);
 }
 

diff --git a/test/Driver/modules.m b/test/Driver/modules.m
index e08de94d0e861a698bf0d528b5fbb78437c554bd..73db4e7e0fcc5a1c8f84f933e95e613ad3cf24fa 100644 (file)
--- a/test/Driver/modules.m
+++ b/test/Driver/modules.m
@@ -30,9 +30,15 @@
 // RUN: %clang -### %s 2>&1 | FileCheck -check-prefix=MODULES_VALIDATE_SYSTEM_HEADERS_DEFAULT %s
 // MODULES_VALIDATE_SYSTEM_HEADERS_DEFAULT-NOT: -fmodules-validate-system-headers
 
+// RUN: %clang -fmodules -fsyntax-only -### %s 2>&1 | FileCheck -check-prefix=MODULES_VALIDATE_SYSTEM_HEADERS_DEFAULT_MOD %s
+// MODULES_VALIDATE_SYSTEM_HEADERS_DEFAULT_MOD: -fmodules-validate-system-headers
+
 // RUN: %clang -fmodules-validate-system-headers -### %s 2>&1 | FileCheck -check-prefix=MODULES_VALIDATE_SYSTEM_HEADERS %s
 // MODULES_VALIDATE_SYSTEM_HEADERS: -fmodules-validate-system-headers
 
+// RUN: %clang -fno-modules-validate-system-headers -### %s 2>&1 | FileCheck -check-prefix=MODULES_VALIDATE_SYSTEM_HEADERS_NOSYSVALID %s
+// MODULES_VALIDATE_SYSTEM_HEADERS_NOSYSVALID-NOT: -fmodules-validate-system-headers
+
 // RUN: %clang -### %s 2>&1 | FileCheck -check-prefix=MODULES_DISABLE_DIAGNOSTIC_VALIDATION_DEFAULT %s
 // MODULES_DISABLE_DIAGNOSTIC_VALIDATION_DEFAULT-NOT: -fmodules-disable-diagnostic-validation