diff --git a/api/sys/README.md b/api/sys/README.md
index 1ecf5117..bb5d672d 100644
--- a/api/sys/README.md
+++ b/api/sys/README.md
@@ -114,6 +114,7 @@ unsafe extern "C" fn on_update(_: *mut c_void) -> i32 { 1 /* `1` means "OK, cont
 [target.thumbv7em-none-eabihf]
 rustflags = [
 	"-Ctarget-cpu=cortex-m7",
+	"-Ctarget-feature=-fp64",
 	"-Clink-args=--emit-relocs",
 	"-Crelocation-model=pic",
 	"-Csoft-float=no",
diff --git a/cargo/tests/crates/simple/with-cfg/.cargo/config.toml b/cargo/tests/crates/simple/with-cfg/.cargo/config.toml
index e8e69aa4..0f801f0f 100644
--- a/cargo/tests/crates/simple/with-cfg/.cargo/config.toml
+++ b/cargo/tests/crates/simple/with-cfg/.cargo/config.toml
@@ -6,6 +6,7 @@ rustflags = ["-C", "target-cpu=native"]
 [target.thumbv7em-none-eabihf]
 rustflags = [
 	"-Ctarget-cpu=cortex-m7",
+	"-Ctarget-feature=-fp64",
 	"-Clink-args=--emit-relocs",
 	"-Crelocation-model=pic",
 	"-Csoft-float=no",
diff --git a/support/utils/src/compile.rs b/support/utils/src/compile.rs
index c0bb456a..5fee016f 100644
--- a/support/utils/src/compile.rs
+++ b/support/utils/src/compile.rs
@@ -21,6 +21,7 @@ pub const GCC_ARGS_LIB: &[&str] = &["-nostartfiles",
 
 pub const RUSTFLAGS_LIB_HOST: &[&str] = &["-Ctarget-cpu=native"];
 pub const RUSTFLAGS_LIB_PLAYDATE: &[&str] = &["-Ctarget-cpu=cortex-m7",
+                                              "-Ctarget-feature=-fp64",
                                               "-Clink-args=--emit-relocs",
                                               "-Crelocation-model=pic",
                                               "-Csoft-float=no",
@@ -32,6 +33,7 @@ pub const RUSTFLAGS_LIB_PLAYDATE: &[&str] = &["-Ctarget-cpu=cortex-m7",
 /// - `-Clink-arg=-T...link_map.ld`
 /// - `-L{libs-search-paths}`
 pub const RUSTFLAGS_BIN_PLAYDATE: &[&str] = &["-Ctarget-cpu=cortex-m7",
+                                              "-Ctarget-feature=-fp64",
                                               "-Clink-args=--emit-relocs",
                                               "-Crelocation-model=pic",
                                               "-Csoft-float=no",