1 files changed, 55 insertions, 6 deletions

diff --git a/Source/cmGlobalNinjaGenerator.cxx b/Source/cmGlobalNinjaGenerator.cxx
index 6c612ab..f74f1e0 100644
--- a/Source/cmGlobalNinjaGenerator.cxx
+++ b/Source/cmGlobalNinjaGenerator.cxx
@@ -17,6 +17,7 @@
 #include "cmLocalNinjaGenerator.h"
 #include "cmMakefile.h"
 #include "cmVersion.h"
+#include "cmAlgorithms.h"
 
 #include <algorithm>
 #include <assert.h>
@@ -183,7 +184,10 @@ void cmGlobalNinjaGenerator::WriteBuild(std::ostream& os,
       i != outputs.end(); ++i)
     {
     build += " " + EncodeIdent(EncodePath(*i), os);
-    this->CombinedBuildOutputs.insert( EncodePath(*i) );
+    if (this->ComputingUnknownDependencies)
+      {
+      this->CombinedBuildOutputs.insert( EncodePath(*i) );
+      }
     }
   build += ":";
 
@@ -281,11 +285,14 @@ cmGlobalNinjaGenerator::WriteCustomCommandBuild(const std::string& command,
                    orderOnly,
                    vars);
 
-  //we need to track every dependency that comes in, since we are trying
-  //to find dependencies that are side effects of build commands
-  for(cmNinjaDeps::const_iterator i = deps.begin(); i != deps.end(); ++i)
+  if (this->ComputingUnknownDependencies)
     {
-    this->CombinedCustomCommandExplicitDependencies.insert( EncodePath(*i) );
+    //we need to track every dependency that comes in, since we are trying
+    //to find dependencies that are side effects of build commands
+    for(cmNinjaDeps::const_iterator i = deps.begin(); i != deps.end(); ++i)
+      {
+      this->CombinedCustomCommandExplicitDependencies.insert(EncodePath(*i));
+      }
     }
 }
 
@@ -477,6 +484,8 @@ cmGlobalNinjaGenerator::cmGlobalNinjaGenerator()
   , CompileCommandsStream(0)
   , Rules()
   , AllDependencies()
+  , ComputingUnknownDependencies(false)
+  , PolicyCMP0058(cmPolicies::WARN)
 {
   // // Ninja is not ported to non-Unix OS yet.
   // this->ForceUnixPaths = true;
@@ -510,6 +519,13 @@ void cmGlobalNinjaGenerator::Generate()
   this->OpenBuildFileStream();
   this->OpenRulesFileStream();
 
+  this->PolicyCMP0058 =
+    this->LocalGenerators[0]->GetMakefile()
+    ->GetPolicyStatus(cmPolicies::CMP0058);
+  this->ComputingUnknownDependencies =
+    (this->PolicyCMP0058 == cmPolicies::OLD ||
+     this->PolicyCMP0058 == cmPolicies::WARN);
+
   this->cmGlobalGenerator::Generate();
 
   this->WriteAssumedSourceDependencies();
@@ -955,6 +971,11 @@ void cmGlobalNinjaGenerator::WriteTargetAliases(std::ostream& os)
 
 void cmGlobalNinjaGenerator::WriteUnknownExplicitDependencies(std::ostream& os)
 {
+  if (!this->ComputingUnknownDependencies)
+    {
+    return;
+    }
+
   // We need to collect the set of known build outputs.
   // Start with those generated by WriteBuild calls.
   // No other method needs this so we can take ownership
@@ -1047,9 +1068,11 @@ void cmGlobalNinjaGenerator::WriteUnknownExplicitDependencies(std::ostream& os)
                       knownDependencies.end(),
                       std::back_inserter(unknownExplicitDepends));
 
-
   std::string const rootBuildDirectory =
       this->GetCMakeInstance()->GetHomeOutputDirectory();
+  bool const inSourceBuild =
+    (rootBuildDirectory == this->GetCMakeInstance()->GetHomeDirectory());
+  std::vector<std::string> warnExplicitDepends;
   for (std::vector<std::string>::const_iterator
        i = unknownExplicitDepends.begin();
        i != unknownExplicitDepends.end();
@@ -1067,8 +1090,34 @@ void cmGlobalNinjaGenerator::WriteUnknownExplicitDependencies(std::ostream& os)
                             "",
                             deps,
                             cmNinjaDeps());
+      if (this->PolicyCMP0058 == cmPolicies::WARN &&
+          !inSourceBuild && warnExplicitDepends.size() < 10)
+        {
+        warnExplicitDepends.push_back(*i);
+        }
       }
    }
+
+  if (!warnExplicitDepends.empty())
+    {
+    std::ostringstream w;
+    w <<
+      (this->GetCMakeInstance()->GetPolicies()->
+       GetPolicyWarning(cmPolicies::CMP0058)) << "\n"
+      "This project specifies custom command DEPENDS on files "
+      "in the build tree that are not specified as the OUTPUT or "
+      "BYPRODUCTS of any add_custom_command or add_custom_target:\n"
+      " " << cmJoin(warnExplicitDepends, "\n ") <<
+      "\n"
+      "For compatibility with versions of CMake that did not have "
+      "the BYPRODUCTS option, CMake is generating phony rules for "
+      "such files to convince 'ninja' to build."
+      "\n"
+      "Project authors should add the missing BYPRODUCTS or OUTPUT "
+      "options to the custom commands that produce these files."
+      ;
+    this->GetCMakeInstance()->IssueMessage(cmake::AUTHOR_WARNING, w.str());
+    }
 }
 
 void cmGlobalNinjaGenerator::WriteBuiltinTargets(std::ostream& os)