Merge topic 'ninja-always-make-object-dirs'

de3dc16b64 cmNinjaTargetGenerator: use `.` for the needed phony order-only dependency
1aa28f3b92 cmNinjaTargetGenerator: ensure that the object output directory exists
4a9613ff9b cmNinjaTargetGenerator: add a method to compute the object directory

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !9105

Source/cmGlobalNinjaGenerator.cxx

@@ -828,6 +828,9 @@ void cmGlobalNinjaGenerator::CheckNinjaFeatures()
     this->NinjaExpectedEncoding = codecvt_Encoding::ANSI;
   }
 #endif
+  this->NinjaSupportsCWDDepend =
+    !cmSystemTools::VersionCompare(cmSystemTools::OP_LESS, this->NinjaVersion,
+                                   RequiredNinjaVersionForCWDDepend());
 }
 
 void cmGlobalNinjaGenerator::CheckNinjaCodePage()
@@ -1996,6 +1999,11 @@ bool cmGlobalNinjaGenerator::SupportsMultilineDepfile() const
   return this->NinjaSupportsMultilineDepfile;
 }
 
+bool cmGlobalNinjaGenerator::SupportsCWDDepend() const
+{
+  return this->NinjaSupportsCWDDepend;
+}
+
 bool cmGlobalNinjaGenerator::WriteTargetCleanAdditional(std::ostream& os)
 {
   const auto& lgr = this->LocalGenerators.at(0);

Source/cmGlobalNinjaGenerator.h

@@ -415,10 +415,12 @@ public:
     return "1.10.2";
   }
   static std::string RequiredNinjaVersionForCodePage() { return "1.11"; }
+  static std::string RequiredNinjaVersionForCWDDepend() { return "1.7"; }
   bool SupportsDirectConsole() const override;
   bool SupportsImplicitOuts() const;
   bool SupportsManifestRestat() const;
   bool SupportsMultilineDepfile() const;
+  bool SupportsCWDDepend() const;
 
   std::string NinjaOutputPath(std::string const& path) const;
   bool HasOutputPathPrefix() const { return !this->OutputPathPrefix.empty(); }
@@ -597,6 +599,7 @@ private:
   bool NinjaSupportsMultipleOutputs = false;
   bool NinjaSupportsMetadataOnRegeneration = false;
   bool NinjaSupportsCodePage = false;
+  bool NinjaSupportsCWDDepend = false;
 
   codecvt_Encoding NinjaExpectedEncoding = codecvt_Encoding::None;
 

Source/cmNinjaTargetGenerator.cxx

@@ -411,28 +411,29 @@ std::string cmNinjaTargetGenerator::GetCompiledSourceNinjaPath(
   return this->ConvertToNinjaAbsPath(source->GetFullPath());
 }
 
-std::string cmNinjaTargetGenerator::GetObjectFilePath(
-  cmSourceFile const* source, const std::string& config) const
+std::string cmNinjaTargetGenerator::GetObjectFileDir(
+  const std::string& config) const
 {
   std::string path = this->LocalGenerator->GetHomeRelativeOutputPath();
   if (!path.empty()) {
     path += '/';
   }
-  std::string const& objectName = this->GeneratorTarget->GetObjectName(source);
-  path += cmStrCat(
-    this->LocalGenerator->GetTargetDirectory(this->GeneratorTarget),
-    this->GetGlobalGenerator()->ConfigDirectory(config), '/', objectName);
+  path +=
+    cmStrCat(this->LocalGenerator->GetTargetDirectory(this->GeneratorTarget),
+             this->GetGlobalGenerator()->ConfigDirectory(config));
   return path;
 }
 
+std::string cmNinjaTargetGenerator::GetObjectFilePath(
+  cmSourceFile const* source, const std::string& config) const
+{
+  std::string const& objectName = this->GeneratorTarget->GetObjectName(source);
+  return cmStrCat(this->GetObjectFileDir(config), '/', objectName);
+}
+
 std::string cmNinjaTargetGenerator::GetBmiFilePath(
   cmSourceFile const* source, const std::string& config) const
 {
-  std::string path = this->LocalGenerator->GetHomeRelativeOutputPath();
-  if (!path.empty()) {
-    path += '/';
-  }
-
   auto& importedConfigInfo = this->Configs.at(config).ImportedCxxModules;
   if (!importedConfigInfo.Initialized()) {
     std::string configUpper = cmSystemTools::UpperCase(config);
@@ -444,10 +445,7 @@ std::string cmNinjaTargetGenerator::GetBmiFilePath(
   std::string bmiName =
     importedConfigInfo.BmiNameForSource(source->GetFullPath());
 
-  path += cmStrCat(
-    this->LocalGenerator->GetTargetDirectory(this->GeneratorTarget),
-    this->GetGlobalGenerator()->ConfigDirectory(config), '/', bmiName);
-  return path;
+  return cmStrCat(this->GetObjectFileDir(config), '/', bmiName);
 }
 
 std::string cmNinjaTargetGenerator::GetClangTidyReplacementsFilePath(
@@ -1025,6 +1023,15 @@ void cmNinjaTargetGenerator::WriteObjectBuildStatements(
     }
   }
 
+  if (!this->GetGlobalGenerator()->SupportsCWDDepend()) {
+    // Ensure that the object directory exists. If there are no objects in the
+    // target (e.g., an empty `OBJECT` library), the directory is still listed
+    // as an order-only depends in the build files. Alternate `ninja`
+    // implementations may not allow this (such as `samu`). See #25526.
+    auto const objectDir = this->GetObjectFileDir(config);
+    this->EnsureDirectoryExists(objectDir);
+  }
+
   {
     cmNinjaBuild build("phony");
     build.Comment =
@@ -1099,11 +1106,15 @@ void cmNinjaTargetGenerator::WriteObjectBuildStatements(
     // that "output ... of phony edge with no inputs doesn't exist" and
     // consider the phony output "dirty".
     if (orderOnlyDeps.empty()) {
-      // Any path that always exists will work here.  It would be nice to
-      // use just "." but that is not supported by Ninja < 1.7.
-      std::string tgtDir = cmStrCat(
-        this->LocalGenerator->GetCurrentBinaryDirectory(), '/',
-        this->LocalGenerator->GetTargetDirectory(this->GeneratorTarget));
+      std::string tgtDir;
+      if (this->GetGlobalGenerator()->SupportsCWDDepend()) {
+        tgtDir = ".";
+      } else {
+        // Any path that always exists will work here.
+        tgtDir = cmStrCat(
+          this->LocalGenerator->GetCurrentBinaryDirectory(), '/',
+          this->LocalGenerator->GetTargetDirectory(this->GeneratorTarget));
+      }
       orderOnlyDeps.push_back(this->ConvertToNinjaPath(tgtDir));
     }
 

Source/cmNinjaTargetGenerator.h

@@ -128,6 +128,7 @@ protected:
   /// @return the source file path for the given @a source.
   std::string GetCompiledSourceNinjaPath(cmSourceFile const* source) const;
 
+  std::string GetObjectFileDir(const std::string& config) const;
   /// @return the object file path for the given @a source.
   std::string GetObjectFilePath(cmSourceFile const* source,
                                 const std::string& config) const;