diff --git a/src/header/float/cbindgen.toml b/src/header/float/cbindgen.toml
index b08945514d..1936479790 100644
--- a/src/header/float/cbindgen.toml
+++ b/src/header/float/cbindgen.toml
@@ -42,6 +42,9 @@ after_includes = """
 
 #define LDBL_HAS_SUBNORM 1
 #define LDBL_DECIMAL_DIG DECIMAL_DIG
+#define LDBL_DIG 18
+#define LDBL_MIN_10_EXP (-4931)
+#define LDBL_MAX_10_EXP 4932
 
 // TODO: Support more architectures than x86_64 here:
 #define LDBL_TRUE_MIN 3.6451995318824746025e-4951L
@@ -53,6 +56,8 @@ after_includes = """
 #define LDBL_MIN_EXP (-16381)
 #define LDBL_MAX_EXP 16384
 
+#define DECIMAL_DIG 21
+
 #endif // _RELIBC_BITS_FLOAT_H
 """
 language = "C"