VS: Fix regression causing source accumulation across Fortran projects

Since commit de2afc5d53 (cmMakeFile: Remove source groups argument from
`FindSourceGroup`, 2025-11-07, v4.3.0-rc1~414^2~2) we share source group
assignments across targets to avoid copying and repeated work.  However,
the VS 7 generator, still used for Fortran, relies on per-target
per-group source lists.  Build them specifically for that case.

The deprecated Eclipse CDT4 extra generator had the same regression,
so fix it too.

Fixes: #27779

Source/cmExtraEclipseCDT4Generator.cxx

@@ -463,7 +463,8 @@ void cmExtraEclipseCDT4Generator::CreateProjectFile()
 }
 
 void cmExtraEclipseCDT4Generator::WriteGroups(
-  SourceGroupVector const& sourceGroups, std::string& linkName,
+  SourceGroupVector const& sourceGroups,
+  cmSourceGroupFiles const& sourceGroupFiles, std::string& linkName,
   cmXMLWriter& xml)
 {
   for (auto const& sg : sourceGroups) {
@@ -475,10 +476,11 @@ void cmExtraEclipseCDT4Generator::WriteGroups(
       xml, linkName3, "virtual:/virtual", VirtualFolder);
     SourceGroupVector const& children = sg->GetGroupChildren();
     if (!children.empty()) {
-      this->WriteGroups(children, linkName, xml);
+      this->WriteGroups(children, sourceGroupFiles, linkName, xml);
     }
-    std::vector<cmSourceFile const*> sFiles = sg->GetSourceFiles();
-    for (cmSourceFile const* file : sFiles) {
+    std::vector<cmSourceFile const*> const& sourceFiles =
+      sourceGroupFiles.GetSourceFiles(sg.get());
+    for (cmSourceFile const* file : sourceFiles) {
       std::string const& fullPath = file->GetFullPath();
 
       if (!cmSystemTools::FileIsDirectory(fullPath)) {
@@ -521,17 +523,18 @@ void cmExtraEclipseCDT4Generator::CreateLinksForTargets(cmXMLWriter& xml)
             break; // skip generating the linked resources to the source files
           }
           // get the files from the source lists then add them to the groups
+          cmSourceGroupFiles sourceGroupFiles;
           std::vector<cmSourceFile*> files;
           target->GetSourceFiles(
             files, makefile->GetSafeDefinition("CMAKE_BUILD_TYPE"));
           for (cmSourceFile* sf : files) {
             // Add the file to the list of sources.
-            std::string const& source = sf->ResolveFullPath();
-            cmSourceGroup* sourceGroup = lg->FindSourceGroup(source);
-            sourceGroup->AssignSource(sf);
+            sourceGroupFiles.Add(lg->FindSourceGroup(sf->ResolveFullPath()),
+                                 sf);
           }
 
-          this->WriteGroups(makefile->GetSourceGroups(), linkName2, xml);
+          this->WriteGroups(makefile->GetSourceGroups(), sourceGroupFiles,
+                            linkName2, xml);
         } break;
         // ignore all others:
         default:

Source/cmExtraEclipseCDT4Generator.h

@@ -88,6 +88,7 @@ private:
                         cmLocalGenerator& lg);
 
   void WriteGroups(SourceGroupVector const& sourceGroups,
+                   cmSourceGroupFiles const& sourceGroupFiles,
                    std::string& linkName, cmXMLWriter& xml);
   void CreateLinksToSubprojects(cmXMLWriter& xml, std::string const& baseDir);
   void CreateLinksForTargets(cmXMLWriter& xml);

Source/cmLocalVisualStudio7Generator.cxx

@@ -1386,6 +1386,8 @@ void cmLocalVisualStudio7Generator::WriteVCProjFile(std::ostream& fout,
   AllConfigSources sources;
   sources.Sources = target->GetAllConfigSources();
 
+  cmSourceGroupFiles sourceGroupFiles;
+
   // Add CMakeLists.txt file with rule to re-run CMake for user convenience.
   if (target->GetType() != cmStateEnums::GLOBAL_TARGET &&
       target->GetName() != CMAKE_CHECK_BUILD_SYSTEM_TARGET) {
@@ -1423,9 +1425,7 @@ void cmLocalVisualStudio7Generator::WriteVCProjFile(std::ostream& fout,
       }
     }
     // Add the file to the list of sources.
-    std::string const source = sf->GetFullPath();
-    cmSourceGroup* sourceGroup = this->FindSourceGroup(source);
-    sourceGroup->AssignSource(sf);
+    sourceGroupFiles.Add(this->FindSourceGroup(sf->GetFullPath()), sf);
   }
 
   // open the project
@@ -1438,7 +1438,8 @@ void cmLocalVisualStudio7Generator::WriteVCProjFile(std::ostream& fout,
   // Loop through every source group.
   SourceGroupVector const& sourceGroups = this->Makefile->GetSourceGroups();
   for (auto const& sg : sourceGroups) {
-    this->WriteGroup(sg.get(), target, fout, libName, configs, sources);
+    this->WriteGroup(sg.get(), target, fout, libName, configs, sources,
+                     sourceGroupFiles);
   }
 
   fout << "\t</Files>\n";
@@ -1648,11 +1649,12 @@ std::string cmLocalVisualStudio7Generator::ComputeLongestObjectDirectory(
 bool cmLocalVisualStudio7Generator::WriteGroup(
   cmSourceGroup const* sg, cmGeneratorTarget* target, std::ostream& fout,
   std::string const& libName, std::vector<std::string> const& configs,
-  AllConfigSources const& sources)
+  AllConfigSources const& sources, cmSourceGroupFiles const& sourceGroupFiles)
 {
   cmGlobalVisualStudio7Generator* gg =
     static_cast<cmGlobalVisualStudio7Generator*>(this->GlobalGenerator);
-  std::vector<cmSourceFile const*> const& sourceFiles = sg->GetSourceFiles();
+  std::vector<cmSourceFile const*> const& sourceFiles =
+    sourceGroupFiles.GetSourceFiles(sg);
   SourceGroupVector const& children = sg->GetGroupChildren();
 
   // Write the children to temporary output.
@@ -1660,7 +1662,7 @@ bool cmLocalVisualStudio7Generator::WriteGroup(
   std::ostringstream tmpOut;
   for (auto const& child : children) {
     if (this->WriteGroup(child.get(), target, tmpOut, libName, configs,
-                         sources)) {
+                         sources, sourceGroupFiles)) {
       hasChildrenWithSources = true;
     }
   }

Source/cmLocalVisualStudio7Generator.h

@@ -23,6 +23,7 @@ class cmLocalVisualStudio7GeneratorInternals;
 class cmMakefile;
 class cmSourceFile;
 class cmSourceGroup;
+class cmSourceGroupFiles;
 
 class cmVS7GeneratorOptions : public cmVisualStudioGeneratorOptions
 {
@@ -147,7 +148,8 @@ private:
   bool WriteGroup(cmSourceGroup const* sg, cmGeneratorTarget* target,
                   std::ostream& fout, std::string const& libName,
                   std::vector<std::string> const& configs,
-                  AllConfigSources const& sources);
+                  AllConfigSources const& sources,
+                  cmSourceGroupFiles const& sourceGroupFiles);
 
   friend class cmLocalVisualStudio7GeneratorFCInfo;
   friend class cmLocalVisualStudio7GeneratorInternals;

Source/cmSourceGroup.cxx

@@ -7,7 +7,6 @@
 #include <cm/memory>
 
 #include "cmGeneratorExpression.h"
-#include "cmSourceFile.h"
 #include "cmStringAlgorithms.h"
 
 class cmSourceGroupInternals
@@ -85,21 +84,11 @@ bool cmSourceGroup::MatchesFiles(std::string const& name) const
   return this->GroupFiles.find(name) != this->GroupFiles.cend();
 }
 
-void cmSourceGroup::AssignSource(cmSourceFile const* sf)
-{
-  this->SourceFiles.push_back(sf);
-}
-
 std::set<std::string> const& cmSourceGroup::GetGroupFiles() const
 {
   return this->GroupFiles;
 }
 
-std::vector<cmSourceFile const*> const& cmSourceGroup::GetSourceFiles() const
-{
-  return this->SourceFiles;
-}
-
 void cmSourceGroup::AddChild(std::unique_ptr<cmSourceGroup> child)
 {
   this->Internal->GroupChildren.push_back(std::move(child));
@@ -196,3 +185,19 @@ cmSourceGroup* cmSourceGroup::FindSourceGroup(std::string const& source,
   // Shouldn't get here, but just in case, return the default group.
   return groups.data()->get();
 }
+
+void cmSourceGroupFiles::Add(cmSourceGroup const* sg, cmSourceFile const* sf)
+{
+  this->SourceFiles[sg].push_back(sf);
+}
+
+std::vector<cmSourceFile const*> const& cmSourceGroupFiles::GetSourceFiles(
+  cmSourceGroup const* sg) const
+{
+  auto i = this->SourceFiles.find(sg);
+  if (i != this->SourceFiles.end()) {
+    return i->second;
+  }
+  static std::vector<cmSourceFile const*> const empty;
+  return empty;
+}

Source/cmSourceGroup.h

@@ -4,6 +4,7 @@
 
 #include "cmConfigure.h" // IWYU pragma: keep
 
+#include <map>
 #include <memory>
 #include <set>
 #include <string>
@@ -99,23 +100,11 @@ public:
    */
   cmSourceGroup* MatchChildrenRegex(std::string const& name) const;
 
-  /**
-   * Assign the given source file to this group.  Used only by
-   * generators.
-   */
-  void AssignSource(cmSourceFile const* sf);
-
   /**
    * Get the set of file names explicitly added to this source group.
    */
   std::set<std::string> const& GetGroupFiles() const;
 
-  /**
-   * Get the list of the source files that have been assigned to this
-   * source group.
-   */
-  std::vector<cmSourceFile const*> const& GetSourceFiles() const;
-
   SourceGroupVector const& GetGroupChildren() const;
 
   /**
@@ -142,11 +131,18 @@ private:
    */
   std::set<std::string> GroupFiles;
 
-  /**
-   * Vector of all source files that have been assigned to
-   * this group.
-   */
-  std::vector<cmSourceFile const*> SourceFiles;
-
   std::unique_ptr<cmSourceGroupInternals> Internal;
 };
+
+/** \class cmSourceGroup
+ * \brief Used by generators to organize a target's sources into groups.
+ */
+class cmSourceGroupFiles
+{
+  std::map<cmSourceGroup const*, std::vector<cmSourceFile const*>> SourceFiles;
+
+public:
+  void Add(cmSourceGroup const* sg, cmSourceFile const* sf);
+  std::vector<cmSourceFile const*> const& GetSourceFiles(
+    cmSourceGroup const* sg) const;
+};