From 0c6387f7599b33436519859757391ea9133c5df8 Mon Sep 17 00:00:00 2001
From: Richard Smith <richard-llvm@metafoo.co.uk>
Date: Tue, 9 Dec 2014 00:14:36 +0000
Subject: [PATCH] [modules] If the same .pcm file is imported via two different
 paths, don't complain that the contained modules are defined twice.

llvm-svn: 223724
---
 clang/lib/Frontend/CompilerInstance.cpp       |  4 ++-
 clang/test/Modules/explicit-build-relpath.cpp | 49 +++++++++++++++++++++++++++
 2 files changed, 52 insertions(+), 1 deletion(-)
 create mode 100644 clang/test/Modules/explicit-build-relpath.cpp

diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index a5165ad..93a34b7 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -1300,7 +1300,9 @@ bool CompilerInstance::loadModuleFile(StringRef FileName) {
         TopFileIsModule = true;
 
       auto &ModuleFile = CI.ModuleFileOverrides[ModuleName];
-      if (!ModuleFile.empty() && ModuleFile != ModuleFileStack.back())
+      if (!ModuleFile.empty() &&
+          CI.getFileManager().getFile(ModuleFile) !=
+              CI.getFileManager().getFile(ModuleFileStack.back()))
         CI.getDiagnostics().Report(SourceLocation(),
                                    diag::err_conflicting_module_files)
             << ModuleName << ModuleFile << ModuleFileStack.back();
diff --git a/clang/test/Modules/explicit-build-relpath.cpp b/clang/test/Modules/explicit-build-relpath.cpp
new file mode 100644
index 0000000..d9c1566
--- /dev/null
+++ b/clang/test/Modules/explicit-build-relpath.cpp
@@ -0,0 +1,49 @@
+// REQUIRES: shell
+//
+// RUN: rm -rf %t
+// RUN: mkdir %t
+// RUN: cd %t
+
+// ----------------------
+// Build modules A and B.
+// RUN: %clang_cc1 -x c++ -std=c++11 -fmodules -fmodules-cache-path=%t -Rmodule-build -fno-modules-error-recovery \
+// RUN:            -fmodule-name=a -emit-module %S/Inputs/explicit-build/module.modulemap -o a.pcm
+//
+// RUN: %clang_cc1 -x c++ -std=c++11 -fmodules -fmodules-cache-path=%t -Rmodule-build -fno-modules-error-recovery \
+// RUN:            -fmodule-file=a.pcm \
+// RUN:            -fmodule-name=b -emit-module %S/Inputs/explicit-build/module.modulemap -o b-rel.pcm
+//
+// RUN: %clang_cc1 -x c++ -std=c++11 -fmodules -fmodules-cache-path=%t -Rmodule-build -fno-modules-error-recovery \
+// RUN:            -fmodule-file=%t/a.pcm \
+// RUN:            -fmodule-name=b -emit-module %S/Inputs/explicit-build/module.modulemap -o b-abs.pcm
+
+// ------------------------------------------
+// Mix and match relative and absolute paths.
+// RUN: %clang_cc1 -x c++ -std=c++11 -fmodules -fmodules-cache-path=%t -Rmodule-build -fno-modules-error-recovery \
+// RUN:            -I%S/Inputs/explicit-build \
+// RUN:            -fmodule-file=%t/a.pcm \
+// RUN:            -fmodule-file=a.pcm \
+// RUN:            -verify %s
+//
+// RUN: %clang_cc1 -x c++ -std=c++11 -fmodules -fmodules-cache-path=%t -Rmodule-build -fno-modules-error-recovery \
+// RUN:            -I%S/Inputs/explicit-build \
+// RUN:            -fmodule-file=%t/a.pcm \
+// RUN:            -fmodule-file=b-rel.pcm \
+// RUN:            -verify %s
+//
+// RUN: %clang_cc1 -x c++ -std=c++11 -fmodules -fmodules-cache-path=%t -Rmodule-build -fno-modules-error-recovery \
+// RUN:            -I%S/Inputs/explicit-build \
+// RUN:            -fmodule-file=a.pcm \
+// RUN:            -fmodule-file=b-abs.pcm \
+// RUN:            -verify %s
+//
+// RUN: not %clang_cc1 -x c++ -std=c++11 -fmodules -fmodules-cache-path=%t -Rmodule-build -fno-modules-error-recovery \
+// RUN:            -I%S/Inputs/explicit-build \
+// RUN:            -fmodule-file=b-rel.pcm \
+// RUN:            -fmodule-file=b-abs.pcm \
+// RUN:            -verify %s 2>&1 | FileCheck %s
+// CHECK: module 'b' is defined in both '{{.*}}b-rel.pcm' and '{{.*}}b-abs.pcm'
+
+#include "a.h"
+static_assert(a == 1, "");
+// expected-no-diagnostics
-- 
2.7.4