diff --git a/chc/cmdline/ParseManager.py b/chc/cmdline/ParseManager.py
index 8472c50..5a0fc71 100644
--- a/chc/cmdline/ParseManager.py
+++ b/chc/cmdline/ParseManager.py
@@ -33,6 +33,8 @@
 import shlex
 import shutil
 
+from pathlib import Path
+
 import xml.etree.ElementTree as ET
 
 from typing import Any, Dict, List, Optional, Tuple
@@ -77,6 +79,7 @@ def __init__(
             verbose: bool = True,
             keepUnused: bool = False,
             tgtplatform: str = "-m64",
+            preprocessed_path: str = "",
     ) -> None:
         """Initialize paths to code, results, and parser executable.
 
@@ -109,6 +112,7 @@ def __init__(
                 + ". Target platform is set to -m64"
             )
             self._tgtplatform = "-m64"
+        self._preprocessed_path = preprocessed_path
         self.config = Config()
 
     @property
@@ -261,22 +265,36 @@ def preprocess_file_with_cc(
         if mac:
             cmd = cmd[:1] + macoptions + cmd[1:]
         cmd = cmd[:1] + moreoptions + cmd[1:]
+
+        real_ifile = None
+        if self._preprocessed_path:
+            path = Path(self._preprocessed_path) / ifilename
+            path = path.resolve()
+            if path.is_file():
+                real_ifile = path
+
         chklogger.logger.info("Changing directory to %s", self.projectpath)
         os.chdir(self.projectpath)
-        if self.verbose:
-            chklogger.logger.info("Preprocess file: " + str(cmd))
-            p = subprocess.call(
-                cmd, cwd=self.projectpath, stderr=subprocess.STDOUT)
-            if p != 0:
-                chklogger.logger.warning("Result of preprocessing: " + str(p))
+        if real_ifile:
+            try:
+                shutil.copy(real_ifile, ifilename)
+            except shutil.SameFileError:
+                pass
         else:
-            chklogger.logger.info("Preprocess file: " + str(cmd))
-            subprocess.call(
-                cmd,
-                cwd=self.projectpath,
-                stdout=open(os.devnull, "w"),
-                stderr=subprocess.STDOUT,
-            )
+            if self.verbose:
+                chklogger.logger.info("Preprocess file: " + str(cmd))
+                p = subprocess.call(
+                    cmd, cwd=self.projectpath, stderr=subprocess.STDOUT)
+                if p != 0:
+                    chklogger.logger.warning("Result of preprocessing: " + str(p))
+            else:
+                chklogger.logger.info("Preprocess file: " + str(cmd))
+                subprocess.call(
+                    cmd,
+                    cwd=self.projectpath,
+                    stdout=open(os.devnull, "w"),
+                    stderr=subprocess.STDOUT,
+                )
         if copyfiles:
             tgtcfilename = os.path.join(self.savedsourcepath, cfilename)
             tgtifilename = os.path.join(self.savedsourcepath, ifilename)
@@ -367,37 +385,50 @@ def preprocess(
             ecommand.append("-fno-asm")
             self.set_platform(ecommand)
 
-            # issue modified command to produce i files
-            if self.verbose:
-                print("\nIssue command: " + str(ecommand) + "\n")
-                resultcode = subprocess.call(
-                    ecommand,
-                    cwd=ccommand["directory"],
-                    stderr=subprocess.STDOUT
-                )
-                print("result: " + str(resultcode))
+            real_ifile = None
+            if self._preprocessed_path:
+                path = Path(self._preprocessed_path) / ifilename
+                path = path.resolve()
+                if path.is_file():
+                    real_ifile = path
+
+            if real_ifile:
+                try:
+                    shutil.copy(real_ifile, ifilename)
+                except shutil.SameFileError:
+                    pass
             else:
-                subprocess.call(
-                    ecommand,
-                    cwd=ccommand["directory"],
-                    stdout=open(os.devnull, "w"),
-                    stderr=subprocess.STDOUT,
-                )
-
-            # issue original command
-            if self.verbose:
-                print("\nIssue original command: " + str(command) + "\n")
-                resultcode = subprocess.call(
-                    command, cwd=ccommand["directory"], stderr=subprocess.STDOUT
-                )
-                print("result: " + str(resultcode))
-            else:
-                subprocess.call(
-                    command,
-                    cwd=ccommand["directory"],
-                    stdout=open(os.devnull, "w"),
-                    stderr=subprocess.STDOUT,
-                )
+                # issue modified command to produce i files
+                if self.verbose:
+                    print("\nIssue command: " + str(ecommand) + "\n")
+                    resultcode = subprocess.call(
+                        ecommand,
+                        cwd=ccommand["directory"],
+                        stderr=subprocess.STDOUT
+                    )
+                    print("result: " + str(resultcode))
+                else:
+                    subprocess.call(
+                        ecommand,
+                        cwd=ccommand["directory"],
+                        stdout=open(os.devnull, "w"),
+                        stderr=subprocess.STDOUT,
+                    )
+
+                # issue original command
+                if self.verbose:
+                    print("\nIssue original command: " + str(command) + "\n")
+                    resultcode = subprocess.call(
+                        command, cwd=ccommand["directory"], stderr=subprocess.STDOUT
+                    )
+                    print("result: " + str(resultcode))
+                else:
+                    subprocess.call(
+                        command,
+                        cwd=ccommand["directory"],
+                        stdout=open(os.devnull, "w"),
+                        stderr=subprocess.STDOUT,
+                    )
 
             if copyfiles:
                 tgtcfilename = os.path.join(
diff --git a/chc/cmdline/c_file/cfileutil.py b/chc/cmdline/c_file/cfileutil.py
index 0075824..52231ba 100644
--- a/chc/cmdline/c_file/cfileutil.py
+++ b/chc/cmdline/c_file/cfileutil.py
@@ -124,6 +124,7 @@ def cfile_parse_file(args: argparse.Namespace) -> NoReturn:
     loglevel: str = args.loglevel
     logfilename: Optional[str] = args.logfilename
     logfilemode: str = args.logfilemode
+    preprocessed_path: str = args.preprocessed_path
 
     try:
         UF.check_parser()
@@ -159,7 +160,8 @@ def cfile_parse_file(args: argparse.Namespace) -> NoReturn:
     chklogger.logger.info("Target path: %s", targetpath)
 
     parsemanager = ParseManager(
-        projectpath, projectname, targetpath, keep_system_includes=keep_system_includes)
+        projectpath, projectname, targetpath, keep_system_includes=keep_system_includes,
+        preprocessed_path=preprocessed_path)
     parsemanager.remove_semantics()
     parsemanager.initialize_paths()
 
diff --git a/chc/cmdline/c_project/cprojectutil.py b/chc/cmdline/c_project/cprojectutil.py
index b268c25..df08da2 100644
--- a/chc/cmdline/c_project/cprojectutil.py
+++ b/chc/cmdline/c_project/cprojectutil.py
@@ -121,6 +121,7 @@ def cproject_parse_project(args: argparse.Namespace) -> NoReturn:
     loglevel: str = args.loglevel
     logfilename: Optional[str] = args.logfilename
     logfilemode: str = args.logfilemode
+    preprocessed_path: str = args.preprocessed_path
 
     try:
         UF.check_parser()
@@ -168,7 +169,8 @@ def cproject_parse_project(args: argparse.Namespace) -> NoReturn:
         projectpath,
         projectname,
         targetpath,
-        keep_system_includes=keep_system_includes)
+        keep_system_includes=keep_system_includes,
+        preprocessed_path=preprocessed_path)
     parsemanager.remove_semantics()
     parsemanager.initialize_paths()
     exitcode = parsemanager.parse_with_ccommands(compilecommands, copyfiles=True)
diff --git a/chc/cmdline/chkc b/chc/cmdline/chkc
index 5848e0c..7024a5c 100755
--- a/chc/cmdline/chkc
+++ b/chc/cmdline/chkc
@@ -663,6 +663,9 @@ def parse() -> argparse.Namespace:
         "--keep-system-includes",
         action="store_true",
         help="do not filter out functions from files with absolute file names")
+    cfileparse.add_argument(
+        "--preprocessed-path",
+        help="directory that contains preprocessed source files")
     cfileparse.add_argument(
         "--loglevel", "-log",
         choices=UL.LogLevel.options(),
@@ -1491,6 +1494,9 @@ def parse() -> argparse.Namespace:
         "--keep-system-includes",
         action="store_true",
         help="don't filter out functions from files with absolute filenames")
+    cprojectparse.add_argument(
+        "--preprocessed-path",
+        help="directory that contains preprocessed source files")
     cprojectparse.add_argument(
         "--loglevel", "-log",
         choices=UL.LogLevel.options(),