Remove d32 feature from 32-bit Arm targets

compiler/rustc_target/src/spec/targets/arm_unknown_linux_gnueabihf.rs

@@ -17,7 +17,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
-            features: "+strict-align,+v6,+vfp2".into(),
+            features: "+strict-align,+v6,+vfp2,-d32".into(),
             max_atomic_width: Some(64),
             mcount: "\u{1}__gnu_mcount_nc".into(),
             llvm_mcount_intrinsic: Some("llvm.arm.gnu.eabi.mcount".into()),

compiler/rustc_target/src/spec/targets/arm_unknown_linux_musleabihf.rs

@@ -17,7 +17,7 @@ pub(crate) fn target() -> Target {
             llvm_floatabi: Some(FloatAbi::Hard),
             // Most of these settings are copied from the arm_unknown_linux_gnueabihf
             // target.
-            features: "+strict-align,+v6,+vfp2".into(),
+            features: "+strict-align,+v6,+vfp2,-d32".into(),
             max_atomic_width: Some(64),
             mcount: "\u{1}mcount".into(),
             // FIXME(compiler-team#422): musl targets should be dynamically linked by default.

compiler/rustc_target/src/spec/targets/armv6_unknown_freebsd.rs

@@ -15,7 +15,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
-            features: "+v6,+vfp2".into(),
+            features: "+v6,+vfp2,-d32".into(),
             max_atomic_width: Some(64),
             mcount: "\u{1}__gnu_mcount_nc".into(),
             llvm_mcount_intrinsic: Some("llvm.arm.gnu.eabi.mcount".into()),

compiler/rustc_target/src/spec/targets/armv6_unknown_netbsd_eabihf.rs

@@ -15,7 +15,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
-            features: "+v6,+vfp2".into(),
+            features: "+v6,+vfp2,-d32".into(),
             max_atomic_width: Some(64),
             mcount: "__mcount".into(),
             ..base::netbsd::opts()

compiler/rustc_target/src/spec/targets/armv7_linux_androideabi.rs

@@ -28,7 +28,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::Eabi,
             llvm_floatabi: Some(FloatAbi::Soft),
-            features: "+v7,+thumb-mode,+thumb2,+vfp3d16,-neon".into(),
+            features: "-d32,+v7,+thumb-mode,+thumb2,+vfp3d16".into(),
             supported_sanitizers: SanitizerSet::ADDRESS,
             max_atomic_width: Some(64),
             ..base

compiler/rustc_target/src/spec/targets/armv7_unknown_freebsd.rs

@@ -15,7 +15,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "-d32,+v7,+vfp3d16,+thumb2".into(),
             max_atomic_width: Some(64),
             mcount: "\u{1}__gnu_mcount_nc".into(),
             ..base::freebsd::opts()

compiler/rustc_target/src/spec/targets/armv7_unknown_linux_gnueabihf.rs

@@ -21,7 +21,7 @@ pub(crate) fn target() -> Target {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
             // Info about features at https://wiki.debian.org/ArmHardFloatPort
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "-d32,+v7,+vfp3d16,+thumb2".into(),
             max_atomic_width: Some(64),
             mcount: "\u{1}__gnu_mcount_nc".into(),
             llvm_mcount_intrinsic: Some("llvm.arm.gnu.eabi.mcount".into()),

compiler/rustc_target/src/spec/targets/armv7_unknown_linux_musleabihf.rs

@@ -20,7 +20,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "-d32,+v7,+vfp3d16,+thumb2".into(),
             max_atomic_width: Some(64),
             mcount: "\u{1}mcount".into(),
             // FIXME(compiler-team#422): musl targets should be dynamically linked by default.

compiler/rustc_target/src/spec/targets/armv7_unknown_linux_uclibceabihf.rs

@@ -19,7 +19,7 @@ pub(crate) fn target() -> Target {
 
         options: TargetOptions {
             // Info about features at https://wiki.debian.org/ArmHardFloatPort
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "-d32,+v7,+vfp3d16,+thumb2".into(),
             cpu: "generic".into(),
             max_atomic_width: Some(64),
             mcount: "_mcount".into(),

compiler/rustc_target/src/spec/targets/armv7_unknown_netbsd_eabihf.rs

@@ -15,7 +15,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "-d32,+v7,+vfp3d16,+thumb2".into(),
             max_atomic_width: Some(64),
             mcount: "__mcount".into(),
             ..base::netbsd::opts()

compiler/rustc_target/src/spec/targets/armv7_wrs_vxworks_eabihf.rs

@@ -16,7 +16,7 @@ pub(crate) fn target() -> Target {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
             // Info about features at https://wiki.debian.org/ArmHardFloatPort
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "-d32,+v7,+vfp3d16,+thumb2".into(),
             max_atomic_width: Some(64),
             ..base::vxworks::opts()
         },

compiler/rustc_target/src/spec/targets/armv7a_kmc_solid_asp3_eabihf.rs

@@ -19,7 +19,7 @@ pub(crate) fn target() -> Target {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
             linker: Some("arm-kmc-eabi-gcc".into()),
-            features: "+v7,+vfp3d16,+thumb2,-neon".into(),
+            features: "-d32,+v7,+vfp3d16,+thumb2".into(),
             relocation_model: RelocModel::Static,
             disable_redzone: true,
             max_atomic_width: Some(64),

compiler/rustc_target/src/spec/targets/armv7a_none_eabihf.rs

@@ -17,7 +17,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
-            features: "+vfp3d16,-neon,+strict-align".into(),
+            features: "-d32,+vfp3d16,+strict-align".into(),
             max_atomic_width: Some(64),
             has_thumb_interworking: true,
             ..base::arm_none::opts()

compiler/rustc_target/src/spec/targets/thumbv7a_none_eabihf.rs

@@ -17,7 +17,7 @@ pub(crate) fn target() -> Target {
         options: TargetOptions {
             cfg_abi: CfgAbi::EabiHf,
             llvm_floatabi: Some(FloatAbi::Hard),
-            features: "+vfp3d16,-neon,+strict-align".into(),
+            features: "-d32,+vfp3d16,+strict-align".into(),
             max_atomic_width: Some(64),
             has_thumb_interworking: true,
             ..base::arm_none::opts()

src/doc/rustc/src/platform-support/arm-linux.md

@@ -215,3 +215,7 @@ export CXX_arm_unknown_linux_gnueabi=arm-linux-gnueabi-g++
 export CC_arm_unknown_linux_gnueabi=arm-linux-gnueabi-gcc
 cargo +nightly build -Zbuild-std --target=arm-unknown-linux-gnueabi
 ```
+
+> **Note**: From version 1.94 up to 1.99, some hardfloat targets required `VFPv3-D32` as a minimum
+> as they erroneously enabled the `d32` feature. Breakage introduced as a result of correcting this
+> can be fixed by passing `-Ctarget-feature=+d32` to Rust.

src/doc/rustc/src/platform-support/arm-none-eabi.md

@@ -202,6 +202,10 @@ Most of `core` should work as expected, with the following notes:
 
 Rust programs are output as ELF files.
 
+> **Note**: From version 1.94 up to 1.99, some hardfloat targets required `VFPv3-D32` as a minimum
+> as they erroneously enabled the `d32` feature. Breakage introduced as a result of correcting this
+> can be fixed by passing `-Ctarget-feature=+d32` to Rust.
+
 [atomic-load]: https://doc.rust-lang.org/stable/core/sync/atomic/struct.AtomicU32.html#method.load
 [atomic-store]: https://doc.rust-lang.org/stable/core/sync/atomic/struct.AtomicU32.html#method.store
 [fetch-add]: https://doc.rust-lang.org/stable/core/sync/atomic/struct.AtomicU32.html#method.fetch_add

src/doc/rustc/src/platform-support/armv7-unknown-linux-gnueabi.md

@@ -38,6 +38,10 @@ ar = "arm-linux-gnu-ar"
 linker = "arm-linux-gnu-gcc"
 ```
 
+> **Note**: From version 1.94 up to 1.99 the hardfloat target required `VFPv3-D32` as a minimum as it
+> erroneously enabled the `d32` feature. Breakage introduced as a result of correcting this can be
+> fixed by passing `-Ctarget-feature=+d32` to Rust.
+
 ## Building Rust programs
 
 These targets is distributed through `rustup`, and otherwise requires no special configuration.

src/doc/rustc/src/platform-support/armv7-unknown-linux-uclibceabihf.md

@@ -44,6 +44,10 @@ cc = "/TOOLCHAIN_PATH/bin/arm-buildroot-linux-uclibcgnueabihf-gcc"
 ./x.py build --stage 2
 ```
 
+> **Note**: From version 1.94 up to 1.99 this target required `VFPv3-D32` as a minimum as it
+> erroneously enabled the `d32` feature. Breakage introduced as a result of correcting this can be
+> fixed by passing `-Ctarget-feature=+d32` to Rust.
+
 ## Building and Running Rust Programs
 
 To test cross-compiled binaries on a `x86_64` system, you can use the `qemu-arm` [userspace emulation](https://qemu-project.gitlab.io/qemu/user/main.html) program.  This avoids having a full emulated ARM system by doing dynamic binary translation and dynamic system call translation.  It lets you run ARM programs directly on your `x86_64` kernel.  It's very convenient!

src/doc/rustc/src/platform-support/armv7a-none-eabi.md

@@ -49,10 +49,10 @@ disabled as needed with `-C target-feature=(+/-)`.
 
 In general, the following four combinations are possible:
 
-- VFPv3-D16, target feature `+vfp3` and `-d32`
-- VFPv3-D32, target feature `+vfp3` and `+d32`
-- VFPv4-D16, target feature `+vfp4` and `-d32`
-- VFPv4-D32, target feature `+vfp4` and `+d32`
+- VFPv3-D16, target default
+- VFPv3-D32, target feature `+d32`
+- VFPv4-D16, llvm target feature `+vfp4d16`
+- VFPv4-D32, target feature `+vfp4`
 
 An Armv7-A processor may optionally include a NEON hardware unit which
 provides Single Instruction Multiple Data (SIMD) operations. The
@@ -63,6 +63,10 @@ You can refer to the [arm-none-eabi](arm-none-eabi.md) documentation for a
 generic guide on target feature and target CPU specification and how to enable
 and disable them via `.cargo/config.toml` file.
 
+> **Note**: From version 1.94 up to 1.99 the hardfloat targets required `VFPv3-D32` as a minimum as
+> they erroneously enabled the `d32` feature. Breakage introduced as a result of correcting this can
+> be fixed by passing `-Ctarget-feature=+d32` to Rust.
+
 [vfp]: https://developer.arm.com/documentation/den0013/0400/Floating-Point/Floating-point-basics-and-the-IEEE-754-standard/ARM-VFP
 
 ## Start-up and Low-Level Code

tests/ui/asm/arm-high-dregs.rs

@@ -0,0 +1,21 @@
+//@ add-minicore
+//@ check-fail
+//@ only-arm
+//@ only-eabihf
+//@ ignore-backends: gcc
+
+// As well as the error message, this also tests that d32 is not enabled by default on arm hardfloat
+// targets
+
+#![feature(f16, no_core)]
+#![crate_type = "rlib"]
+#![no_core]
+
+extern crate minicore;
+use minicore::*;
+
+#[no_mangle]
+pub unsafe fn high(x: f64) {
+    asm!("vmov.f64 d16, d0", in("d16") x);
+    //~^ ERROR register class `dreg` requires at least one of the following target features: d32, neon
+}

tests/ui/asm/arm-high-dregs.stderr

@@ -0,0 +1,8 @@
+error: register class `dreg` requires at least one of the following target features: d32, neon
+  --> $DIR/arm-high-dregs.rs:19:30
+   |
+LL |     asm!("vmov.f64 d16, d0", in("d16") x);
+   |                              ^^^^^^^^^^^
+
+error: aborting due to 1 previous error
+