1 files changed, 34 insertions, 0 deletions
diff --git a/Source/cmGccDepfileReader.cxx b/Source/cmGccDepfileReader.cxx
index eb3511a..96a562e 100644
--- a/Source/cmGccDepfileReader.cxx
+++ b/Source/cmGccDepfileReader.cxx
@@ -4,10 +4,13 @@
 
 #include <type_traits>
 #include <utility>
+#include <vector>
 
 #include <cm/optional>
 
 #include "cmGccDepfileLexerHelper.h"
+#include "cmStringAlgorithms.h"
+#include "cmSystemTools.h"
 
 cm::optional<cmGccDepfileContent> cmReadGccDepfile(const char* filePath)
 {
@@ -17,3 +20,34 @@ cm::optional<cmGccDepfileContent> cmReadGccDepfile(const char* filePath)
   }
   return cm::nullopt;
 }
+
+cm::optional<cmGccDepfileContent> cmReadGccDepfile(const char* filePath,
+                                                   const std::string& prefix)
+{
+  auto deps = cmReadGccDepfile(filePath);
+
+  if (prefix.empty() || !deps) {
+    return deps;
+  }
+
+  for (auto& dep : *deps) {
+    for (auto& rule : dep.rules) {
+      if (!cmSystemTools::FileIsFullPath(rule)) {
+        rule = cmStrCat(prefix, rule);
+      }
+      if (cmSystemTools::FileIsFullPath(rule)) {
+        rule = cmSystemTools::CollapseFullPath(rule);
+      }
+    }
+    for (auto& path : dep.paths) {
+      if (!cmSystemTools::FileIsFullPath(path)) {
+        path = cmStrCat(prefix, path);
+      }
+      if (cmSystemTools::FileIsFullPath(path)) {
+        path = cmSystemTools::CollapseFullPath(path);
+      }
+    }
+  }
+
+  return deps;
+}