diff --git a/README.md b/README.md
index b579c80..38659e2 100644
--- a/README.md
+++ b/README.md
@@ -91,6 +91,8 @@ are some non-default options:
 
 ### Default options
 
+* `--enable-float`, disable with `--disable-float`
+
 * `--with[out]-cmdline`
 * `--with[out]-console`
 * `--with[out]-elf`
diff --git a/configure.ac b/configure.ac
index b9f1d64..908b6e2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -13,6 +13,9 @@ AC_CANONICAL_HOST
 
 
 
+dnl Features (enabled by default)
+AC_ARG_ENABLE([float],        AS_HELP_STRING([--disable-float],       [disable floating-point arithmeric]))
+
 dnl Features (disabled by default)
 AC_ARG_ENABLE([assert],       AS_HELP_STRING([--enable-assert],       [enable runtime assertions]))
 AC_ARG_ENABLE([guard],        AS_HELP_STRING([--enable-guard],        [enable argument guards]))
@@ -71,6 +74,9 @@ AM_CONDITIONAL([ASM_I386],          [test "$host_cpu" = i386])
 AM_CONDITIONAL([ASM_RISCV64],       [test "$host_cpu" = riscv64])
 AM_CONDITIONAL([ASM_X86_64],        [test "$host_cpu" = x86_64])
 
+dnl Features (enabled by default)
+AM_CONDITIONAL([ENABLE_FLOAT],      [test "$enable_float"      != no])
+
 dnl Features (disabled by default)
 AM_CONDITIONAL([ENABLE_ASSERT],     [test "$enable_assert"     = yes])
 AM_CONDITIONAL([ENABLE_GUARD_COND], [test "$enable_guard_cond" = yes])
@@ -102,6 +108,9 @@ AS_IF([test "$host_cpu" = i386],          [AC_DEFINE([ASM_I386],
 AS_IF([test "$host_cpu" = riscv64],       [AC_DEFINE([ASM_RISCV64],               [1], [architecture is RISC-V 64-bit])])
 AS_IF([test "$host_cpu" = x86_64],        [AC_DEFINE([ASM_X86_64],                [1], [architecture is x86_64])])
 
+dnl Features (enabled by default)
+AS_IF([test "$enable_float"       != no], [AC_DEFINE([ENABLE_FLOAT],              [1], [enabled floating-point arithmeric])])
+
 dnl Features (disabled by default)
 AS_IF([test "$enable_assert"      = yes], [AC_DEFINE([KERNAUX_ENABLE_ASSERT],     [1], [enabled runtime assertions])])
 AS_IF([test "$enable_guard_cond"  = yes], [AC_DEFINE([KERNAUX_ENABLE_GUARD_COND], [1], [enabled condition guard])])