Makefiles: Add support of DEPFILE for add_custom_command

Issue: #20286
Fixes: #21415

1 files changed, 86 insertions, 47 deletions

diff --git a/Source/cmDependsCompiler.cxx b/Source/cmDependsCompiler.cxx
index f6e5af8..beb080f 100644
--- a/Source/cmDependsCompiler.cxx
+++ b/Source/cmDependsCompiler.cxx
@@ -19,6 +19,7 @@
 
 #include "cmFileTime.h"
 #include "cmGccDepfileReader.h"
+#include "cmGccDepfileReaderTypes.h"
 #include "cmGlobalUnixMakefileGenerator3.h"
 #include "cmLocalUnixMakefileGenerator3.h"
 #include "cmStringAlgorithms.h"
@@ -86,7 +87,7 @@ bool cmDependsCompiler::CheckDependencies(
     if (!forceReadDeps) {
       depFileTime.Load(depFile);
     }
-    if (forceReadDeps || depFileTime.Newer(internalDepFileTime)) {
+    if (forceReadDeps || depFileTime.Compare(internalDepFileTime) >= 0) {
       status = false;
       if (this->Verbose) {
         cmSystemTools::Stdout(cmStrCat("Dependencies file \"", depFile,
@@ -95,59 +96,92 @@ bool cmDependsCompiler::CheckDependencies(
       }
 
       std::vector<std::string> depends;
-      if (format == "msvc"_s) {
-        cmsys::ifstream fin(depFile.c_str());
-        if (!fin) {
-          continue;
+      if (format == "custom"_s) {
+        std::string prefix;
+        if (this->LocalGenerator->GetCurrentBinaryDirectory() !=
+            this->LocalGenerator->GetBinaryDirectory()) {
+          prefix =
+            cmStrCat(this->LocalGenerator->MaybeConvertToRelativePath(
+                       this->LocalGenerator->GetBinaryDirectory(),
+                       this->LocalGenerator->GetCurrentBinaryDirectory()),
+                     '/');
         }
 
-        std::string line;
-        if (!isValidPath) {
-          // insert source as first dependency
-          depends.push_back(source);
-        }
-        while (cmSystemTools::GetLineFromStream(fin, line)) {
-          depends.emplace_back(std::move(line));
-        }
-      } else {
-        auto deps = cmReadGccDepfile(depFile.c_str());
+        auto deps = cmReadGccDepfile(depFile.c_str(), prefix);
         if (!deps) {
           continue;
         }
 
-        // dependencies generated by the compiler contains only one target
-        depends = std::move(deps->front().paths);
-        if (depends.empty()) {
-          // unexpectedly empty, ignore it and continue
-          continue;
-        }
-
-        // depending of the effective format of the dependencies file generated
-        // by the compiler, the target can be wrongly identified as a
-        // dependency so remove it from the list
-        if (depends.front() == target) {
-          depends.erase(depends.begin());
+        for (auto& entry : *deps) {
+          depends = std::move(entry.paths);
+          if (isValidPath) {
+            cm::erase_if(depends, isValidPath);
+          }
+          // copy depends for each target, except first one, which can be
+          // moved
+          for (auto index = entry.rules.size() - 1; index > 0; --index) {
+            dependencies[entry.rules[index]] = depends;
+          }
+          dependencies[entry.rules.front()] = std::move(depends);
         }
+      } else {
+        if (format == "msvc"_s) {
+          cmsys::ifstream fin(depFile.c_str());
+          if (!fin) {
+            continue;
+          }
 
-        // ensure source file is the first dependency
-        if (depends.front() != source) {
-          cm::erase(depends, source);
+          std::string line;
           if (!isValidPath) {
-            depends.insert(depends.begin(), source);
+            // insert source as first dependency
+            depends.push_back(source);
+          }
+          while (cmSystemTools::GetLineFromStream(fin, line)) {
+            depends.emplace_back(std::move(line));
+          }
+        } else if (format == "gcc"_s) {
+          auto deps = cmReadGccDepfile(depFile.c_str());
+          if (!deps) {
+            continue;
           }
-        } else if (isValidPath) {
-          // remove first dependency because it must not be filtered out
-          depends.erase(depends.begin());
+
+          // dependencies generated by the compiler contains only one target
+          depends = std::move(deps->front().paths);
+          if (depends.empty()) {
+            // unexpectedly empty, ignore it and continue
+            continue;
+          }
+
+          // depending of the effective format of the dependencies file
+          // generated by the compiler, the target can be wrongly identified
+          // as a dependency so remove it from the list
+          if (depends.front() == target) {
+            depends.erase(depends.begin());
+          }
+
+          // ensure source file is the first dependency
+          if (depends.front() != source) {
+            cm::erase(depends, source);
+            if (!isValidPath) {
+              depends.insert(depends.begin(), source);
+            }
+          } else if (isValidPath) {
+            // remove first dependency because it must not be filtered out
+            depends.erase(depends.begin());
+          }
+        } else {
+          // unknown format, ignore it
+          continue;
         }
-      }
 
-      if (isValidPath) {
-        cm::erase_if(depends, isValidPath);
-        // insert source as first dependency
-        depends.insert(depends.begin(), source);
-      }
+        if (isValidPath) {
+          cm::erase_if(depends, isValidPath);
+          // insert source as first dependency
+          depends.insert(depends.begin(), source);
+        }
 
-      dependencies[target] = std::move(depends);
+        dependencies[target] = std::move(depends);
+      }
     }
   }
 
@@ -168,6 +202,8 @@ void cmDependsCompiler::WriteDependencies(
 
   // external dependencies file
   for (auto& node : makeDependencies) {
+    auto target = LocalGenerator->ConvertToMakefilePath(
+      this->LocalGenerator->MaybeConvertToRelativePath(binDir, node.first));
     auto& deps = node.second;
     std::transform(
       deps.cbegin(), deps.cend(), deps.begin(),
@@ -176,13 +212,16 @@ void cmDependsCompiler::WriteDependencies(
           this->LocalGenerator->MaybeConvertToRelativePath(binDir, dep));
       });
 
-    makeDepends << this->LocalGenerator->ConvertToMakefilePath(node.first)
-                << ": " << deps.front();
-    // first dependency is the source, remove it because should not be declared
-    // as phony target
-    deps.erase(deps.begin());
+    bool first_dep = true;
+    makeDepends << target << ": ";
     for (const auto& dep : deps) {
-      makeDepends << ' ' << lineContinue << "  " << dep;
+      if (first_dep) {
+        first_dep = false;
+        makeDepends << dep;
+      } else {
+        makeDepends << ' ' << lineContinue << "  " << dep;
+      }
+
       phonyTargets.emplace(dep.data(), dep.length());
     }
     makeDepends << std::endl << std::endl;