diff --git a/src/reader/wgsl/lexer.cc b/src/reader/wgsl/lexer.cc
index 632aa1f..5fd1ef4 100644
--- a/src/reader/wgsl/lexer.cc
+++ b/src/reader/wgsl/lexer.cc
@@ -216,6 +216,7 @@
       return {Token::Type::kError, source,
               "u32 (" + input_.substr(start, end - start) + ") too large"};
     }
+    pos_ += 1;
     return {source, static_cast<uint32_t>(res)};
   }
 
diff --git a/src/reader/wgsl/lexer_test.cc b/src/reader/wgsl/lexer_test.cc
index 9953443..de64e6f 100644
--- a/src/reader/wgsl/lexer_test.cc
+++ b/src/reader/wgsl/lexer_test.cc
@@ -249,6 +249,9 @@
   EXPECT_EQ(t.line(), 1u);
   EXPECT_EQ(t.column(), 1u);
   EXPECT_EQ(t.to_u32(), params.result);
+
+  t = l.next();
+  EXPECT_TRUE(t.IsEof());
 }
 INSTANTIATE_TEST_SUITE_P(
     LexerTest,