Index: lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp
===================================================================
--- lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp
+++ lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp
@@ -589,9 +589,18 @@
   // - System headers: don't run any checks.
   SourceManager &SM = Ctx->getSourceManager();
   SourceLocation SL = SM.getExpansionLoc(D->getLocation());
+  
+  // Check if the definition of the function declaration has a body.
+  // Update the location if function body is found.
+  if (D->hasBody())
+    SL = D->getBody()->getLocStart();
+
   if (!Opts->AnalyzeAll && !SM.isWrittenInMainFile(SL)) {
     if (SL.isInvalid() || SM.isInSystemHeader(SL))
       return AM_None;
+    // Return the current analysis mode if the location is in the main file.
+    if (SM.isInMainFile(SL))
+      return Mode;
     return Mode & ~AM_Path;
   }
 
Index: test/Analysis/test-include.h
===================================================================
--- test/Analysis/test-include.h
+++ test/Analysis/test-include.h
@@ -0,0 +1 @@
+void test(int * data);
Index: test/Analysis/test-include.c
===================================================================
--- test/Analysis/test-include.c
+++ test/Analysis/test-include.c
@@ -0,0 +1,6 @@
+// RUN: %clang_cc1 -analyze -analyzer-checker=core -verify %s
+#include "test-include.h"
+void test(int * data) {
+  data = 0;
+  *data = 1; // expected-warning{{Dereference of null pointer}}
+}