diff --git a/src/libexpr/lexer.l b/src/libexpr/lexer.l
index 1e196741d..1005f9f7e 100644
--- a/src/libexpr/lexer.l
+++ b/src/libexpr/lexer.l
@@ -1,3 +1,4 @@
+%option 8bit
 %option reentrant bison-bridge bison-locations
 %option align
 %option noyywrap
diff --git a/src/libexpr/meson.build b/src/libexpr/meson.build
index 2e773938d..2b465b85a 100644
--- a/src/libexpr/meson.build
+++ b/src/libexpr/meson.build
@@ -112,6 +112,7 @@ lexer_tab = custom_target(
   ],
   command : [
     'flex',
+    '-Cf', # Use full scanner tables
     '--outfile',
     '@OUTPUT0@',
     '--header-file=' + '@OUTPUT1@',