diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index b6ab49bb548214ce4a17cd0386bc0a1b10f4a2ca..4096c0c0d69f70bc2e6f331d5d9d220c24a3162d 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -12118,7 +12118,7 @@ file_name_acquire (dwarf_file_data **slot, file_name_acquire_data *fnad)
   f = strrchr (f, DIR_SEPARATOR);
 #if defined (DIR_SEPARATOR_2)
   {
-    char *g = strrchr (fi->path, DIR_SEPARATOR_2);
+    const char *g = strrchr (fi->path, DIR_SEPARATOR_2);
 
     if (g != NULL)
       {
diff --git a/libcpp/files.c b/libcpp/files.c
index 3d48c38fc0a8c497c5b1f68471f30edcd7c0a382..b890b8ebf1e07c82dbfe1b32166337b6ea8f73e7 100644
--- a/libcpp/files.c
+++ b/libcpp/files.c
@@ -1693,7 +1693,7 @@ remap_filename (cpp_reader *pfile, _cpp_file *file)
       p = strchr (fname, '/');
 #ifdef HAVE_DOS_BASED_FILE_SYSTEM
       {
-	char *p2 = strchr (fname, '\\');
+	const char *p2 = strchr (fname, '\\');
 	if (!p || (p > p2))
 	  p = p2;
       }