From: Argyrios Kyrtzidis <akyrtzi@gmail.com>
Date: Wed, 3 Apr 2013 05:11:33 +0000 (+0000)
Subject: [modules] If a submodule has re-definitions of the same macro, only the last definiti... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=b2dbfd8669282915c9466ba88c66f9791b946efa;p=clang

[modules] If a submodule has re-definitions of the same macro, only the last definition will be used as the "exported" one.

Fixes rdar://13562262

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178622 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Serialization/ASTWriter.cpp b/lib/Serialization/ASTWriter.cpp
index 033d48c147..6893b5003f 100644
--- a/lib/Serialization/ASTWriter.cpp
+++ b/lib/Serialization/ASTWriter.cpp
@@ -2937,6 +2937,7 @@ class ASTIdentifierTableTrait {
     if (!MD)
       return 0;
 
+    SubmoduleID OrigModID = ModID;
     bool isUndefined = false;
     Optional<bool> isPublic;
     for (; MD; MD = MD->getPrevious()) {
@@ -2954,6 +2955,11 @@ class ASTIdentifierTableTrait {
         isUndefined = false;
         isPublic = Optional<bool>();
       }
+      // We are looking for a definition in a different submodule than the one
+      // that we started with. If a submodule has re-definitions of the same
+      // macro, only the last definition will be used as the "exported" one.
+      if (ModID == OrigModID)
+        continue;
 
       if (DefMacroDirective *DefMD = dyn_cast<DefMacroDirective>(MD)) {
         if (!isUndefined && (!isPublic.hasValue() || isPublic.getValue()))
diff --git a/test/Modules/Inputs/macros_top.h b/test/Modules/Inputs/macros_top.h
index 9c3f3c071f..dd303ffee4 100644
--- a/test/Modules/Inputs/macros_top.h
+++ b/test/Modules/Inputs/macros_top.h
@@ -8,8 +8,8 @@
 
 
 
-
-
+#define TOP_RIGHT_REDEF float
+// The last definition will be exported from the sub-module.
 #define TOP_RIGHT_REDEF int
 
 #define TOP_RIGHT_UNDEF int