diff --git a/src/file.cc b/src/file.cc
index c1f5bb26..fb282a14 100644
--- a/src/file.cc
+++ b/src/file.cc
@@ -217,13 +217,12 @@ MappedFile::MappedFile(StringView filename)
 
     if (st.st_size == 0)
         return;
+    else if (st.st_size > std::numeric_limits<int>::max())
+        throw runtime_error("file is too big");
 
     data = (const char*)mmap(nullptr, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
     if (data == MAP_FAILED)
         throw file_access_error{filename, strerror(errno)};
-
-    if (st.st_size > std::numeric_limits<int>::max())
-        throw runtime_error("file is too big");
 }
 
 MappedFile::~MappedFile()