…ake, r=jieyouxu

Ignore `branch-protection-check-IBT` run-make test

The old Makefile implementation (rust-lang#110304) had an improper comparison which caused the test to never run. However, both the updated Makefile implementation and the rmake implementation fail (missing `.note.gnu.property`). This could be a bug in the original implementation or test flakiness.

Edit: Manually recreating the test case shows that `.note.gnu.property` does not appear in nightly.
```rust
// main.rs
fn main() {
    println!("hello world");
}
```
```sh
$ rustc +nightly -V
rustc 1.81.0-nightly (c1b336c 2024-06-21)
$ rustc +stable -V
rustc 1.79.0 (129f3b9 2024-06-10)
```
```sh
$ rustc +nightly -Zcf-protection=branch -Clink-args=-nostartfiles -Csave-temps "-L$PWD" main.rs -o main
$ llvm-readobj --elf-output-style=GNU -nW main
Displaying notes found in: .note.gnu.build-id
  Owner                Data size        Description
  GNU                  0x00000008       NT_GNU_BUILD_ID (unique build ID bitstring)
    Build ID: bcae34e6431b2a37
```
Compiling without the other flags still does not show `.note.gnu.property`.
```sh
$ rustc +nightly main.rs -o main
$ llvm-readobj --elf-output-style=GNU -nW main
Displaying notes found in: .note.ABI-tag
  Owner                Data size        Description
  GNU                  0x00000010       NT_GNU_ABI_TAG (ABI version tag)
    OS: Linux, ABI: 4.4.0

Displaying notes found in: .note.gnu.build-id
  Owner                Data size        Description
  GNU                  0x00000008       NT_GNU_BUILD_ID (unique build ID bitstring)
    Build ID: d60d5f108b63bf3a
```
Compiling on stable shows `.note.gnu.property`.
```sh
$ rustc +stable main.rs -o main
$ llvm-readobj --elf-output-style=GNU -nW main
Displaying notes found in: .note.gnu.property
  Owner                Data size        Description
  GNU                  0x00000010       NT_GNU_PROPERTY_TYPE_0 (property note)
    Properties:    x86 ISA needed: x86-64-baseline

Displaying notes found in: .note.gnu.build-id
  Owner                Data size        Description
  GNU                  0x00000014       NT_GNU_BUILD_ID (unique build ID bitstring)
    Build ID: 4a494eb578123314e6ff1caf1c8877e27004664f

Displaying notes found in: .note.ABI-tag
  Owner                Data size        Description
  GNU                  0x00000010       NT_GNU_ABI_TAG (ABI version tag)
    OS: Linux, ABI: 4.4.0
```

Part of rust-lang#121876.

r? `@jieyouxu`

Rollup merge of rust-lang#126720 - Rejyr:migrate-branch-protection-rmake, r=jieyouxu

Ignore `branch-protection-check-IBT` run-make test

The old Makefile implementation (rust-lang#110304) had an improper comparison which caused the test to never run. However, both the updated Makefile implementation and the rmake implementation fail (missing `.note.gnu.property`). This could be a bug in the original implementation or test flakiness.

Edit: Manually recreating the test case shows that `.note.gnu.property` does not appear in nightly.
```rust
// main.rs
fn main() {
    println!("hello world");
}
```
```sh
$ rustc +nightly -V
rustc 1.81.0-nightly (c1b336c 2024-06-21)
$ rustc +stable -V
rustc 1.79.0 (129f3b9 2024-06-10)
```
```sh
$ rustc +nightly -Zcf-protection=branch -Clink-args=-nostartfiles -Csave-temps "-L$PWD" main.rs -o main
$ llvm-readobj --elf-output-style=GNU -nW main
Displaying notes found in: .note.gnu.build-id
  Owner                Data size        Description
  GNU                  0x00000008       NT_GNU_BUILD_ID (unique build ID bitstring)
    Build ID: bcae34e6431b2a37
```
Compiling without the other flags still does not show `.note.gnu.property`.
```sh
$ rustc +nightly main.rs -o main
$ llvm-readobj --elf-output-style=GNU -nW main
Displaying notes found in: .note.ABI-tag
  Owner                Data size        Description
  GNU                  0x00000010       NT_GNU_ABI_TAG (ABI version tag)
    OS: Linux, ABI: 4.4.0

Displaying notes found in: .note.gnu.build-id
  Owner                Data size        Description
  GNU                  0x00000008       NT_GNU_BUILD_ID (unique build ID bitstring)
    Build ID: d60d5f108b63bf3a
```
Compiling on stable shows `.note.gnu.property`.
```sh
$ rustc +stable main.rs -o main
$ llvm-readobj --elf-output-style=GNU -nW main
Displaying notes found in: .note.gnu.property
  Owner                Data size        Description
  GNU                  0x00000010       NT_GNU_PROPERTY_TYPE_0 (property note)
    Properties:    x86 ISA needed: x86-64-baseline

Displaying notes found in: .note.gnu.build-id
  Owner                Data size        Description
  GNU                  0x00000014       NT_GNU_BUILD_ID (unique build ID bitstring)
    Build ID: 4a494eb578123314e6ff1caf1c8877e27004664f

Displaying notes found in: .note.ABI-tag
  Owner                Data size        Description
  GNU                  0x00000010       NT_GNU_ABI_TAG (ABI version tag)
    OS: Linux, ABI: 4.4.0
```

Part of rust-lang#121876.

r? `@jieyouxu`

…eck-IBT, r=<try>

Migrate `branch-protection-check-IBT` to rmake.rs

- The Makefile version *never* ran because of Makefile syntax confusion because `ifeq ($(filter x86,$(LLVM_COMPONENTS)),x86_64)` [compares `x86` to `x86_64`, which always evaluates to false](rust-lang#126720 (comment)).
- The test would've always failed because precompiled std is not built with `-Z cf-protection=branch`, but linkers require all input object files to indicate IBT support in order to enable IBT for the executable, which is not the case for std.
- Thus, the test input file is instead changed to a `no_std` program.

The GNU property note was added by rust-lang#110304 in order to address rust-lang#103001.

Partially supersedes rust-lang#129156.
The rmake.rs port was initially authored by `@Rejyr` in rust-lang#126720.
This PR is co-authored with `@Oneirical` and `@Rejyr.`

r? `@bjorn3` or reroll

try-job: x86_64-msvc
try-job: x86_64-apple

…eck-IBT, r=<try>

Migrate `branch-protection-check-IBT` to rmake.rs

- The Makefile version *never* ran because of Makefile syntax confusion because `ifeq ($(filter x86,$(LLVM_COMPONENTS)),x86_64)` [compares `x86` to `x86_64`, which always evaluates to false](rust-lang#126720 (comment)).
- The test would've always failed because precompiled std is not built with `-Z cf-protection=branch`, but linkers require all input object files to indicate IBT support in order to enable IBT for the executable, which is not the case for std.
- Thus, the test input file is instead changed to a `no_std` program.

The GNU property note was added by rust-lang#110304 in order to address rust-lang#103001.

Partially supersedes rust-lang#129156.
The rmake.rs port was initially authored by `@Rejyr` in rust-lang#126720.
This PR is co-authored with `@Oneirical` and `@Rejyr.`

r? `@bjorn3` or reroll

try-job: x86_64-msvc
try-job: x86_64-apple-1
try-job: x86_64-apple-2

…eck-IBT, r=<try>

Migrate `branch-protection-check-IBT` to rmake.rs

- The Makefile version *never* ran because of Makefile syntax confusion because `ifeq ($(filter x86,$(LLVM_COMPONENTS)),x86_64)` [compares `x86` to `x86_64`, which always evaluates to false](rust-lang#126720 (comment)).
- The test would've always failed because precompiled std is not built with `-Z cf-protection=branch`, but linkers require all input object files to indicate IBT support in order to enable IBT for the executable, which is not the case for std.
- Thus, the test input file is instead changed to a `no_std` program.
- Ignore cross-compile for now, because that will require us to build `core` for the cross-compile target (something like `minicore` will not suffice because we need to reach and go past the linking stage).

The GNU property note was added by rust-lang#110304 in order to address rust-lang#103001.

Partially supersedes rust-lang#129156.
The rmake.rs port was initially authored by `@Rejyr` in rust-lang#126720.
This PR is co-authored with `@Oneirical` and `@Rejyr.`

r? `@bjorn3` or reroll

try-job: x86_64-msvc
try-job: x86_64-apple-1
try-job: x86_64-apple-2

…eck-IBT, r=<try>

Migrate `branch-protection-check-IBT` to rmake.rs

- The Makefile version *never* ran because of Makefile syntax confusion because `ifeq ($(filter x86,$(LLVM_COMPONENTS)),x86_64)` [compares `x86` to `x86_64`, which always evaluates to false](rust-lang#126720 (comment)).
- The test would've always failed because precompiled std is not built with `-Z cf-protection=branch`, but linkers require all input object files to indicate IBT support in order to enable IBT for the executable, which is not the case for std.
- Thus, the test input file is instead changed to a `no_std` program.
- Only specifically `x86_64-unknown-linux-gnu` for now.

The GNU property note was added by rust-lang#110304 in order to address rust-lang#103001.

Partially supersedes rust-lang#129156.
The rmake.rs port was initially authored by `@Rejyr` in rust-lang#126720.
This PR is co-authored with `@Oneirical` and `@Rejyr.`

r? `@bjorn3` or reroll

try-job: x86_64-mingw-1
try-job: x86_64-mingw-2
try-job: x86_64-msvc
try-job: x86_64-apple-1
try-job: x86_64-apple-2

…check-IBT, r=lqd

Migrate `branch-protection-check-IBT` to rmake.rs

- The Makefile version *never* ran because of Makefile syntax confusion because `ifeq ($(filter x86,$(LLVM_COMPONENTS)),x86_64)` [compares `x86` to `x86_64`, which always evaluates to false](rust-lang#126720 (comment)).
- The test would've always failed because precompiled std is not built with `-Z cf-protection=branch`, but linkers require all input object files to indicate IBT support in order to enable IBT for the executable, which is not the case for std.
- Thus, the test input file is instead changed to a `no_std` program.
- The test is currently limited to only `x86_64-unknown-linux-gnu` host, there are various other problems when the test is cross-compiled that I didn't want to fix atm, and is left as an exercise for the `-Z cf-protection` implementers.

The GNU property note was added by rust-lang#110304 in order to address rust-lang#103001.

Partially supersedes rust-lang#129156.
The rmake.rs port was initially authored by `@Rejyr` in rust-lang#126720.
This PR is co-authored with `@Oneirical` and `@Rejyr.`

r? `@bjorn3` or reroll

try-job: x86_64-mingw-1
try-job: x86_64-mingw-2
try-job: x86_64-msvc
try-job: x86_64-apple-1
try-job: x86_64-apple-2

Rollup merge of rust-lang#134760 - jieyouxu:enable-branch-protection-check-IBT, r=lqd

Migrate `branch-protection-check-IBT` to rmake.rs

- The Makefile version *never* ran because of Makefile syntax confusion because `ifeq ($(filter x86,$(LLVM_COMPONENTS)),x86_64)` [compares `x86` to `x86_64`, which always evaluates to false](rust-lang#126720 (comment)).
- The test would've always failed because precompiled std is not built with `-Z cf-protection=branch`, but linkers require all input object files to indicate IBT support in order to enable IBT for the executable, which is not the case for std.
- Thus, the test input file is instead changed to a `no_std` program.
- The test is currently limited to only `x86_64-unknown-linux-gnu` host, there are various other problems when the test is cross-compiled that I didn't want to fix atm, and is left as an exercise for the `-Z cf-protection` implementers.

The GNU property note was added by rust-lang#110304 in order to address rust-lang#103001.

Partially supersedes rust-lang#129156.
The rmake.rs port was initially authored by `@Rejyr` in rust-lang#126720.
This PR is co-authored with `@Oneirical` and `@Rejyr.`

r? `@bjorn3` or reroll

try-job: x86_64-mingw-1
try-job: x86_64-mingw-2
try-job: x86_64-msvc
try-job: x86_64-apple-1
try-job: x86_64-apple-2

…check-IBT, r=lqd

Migrate `branch-protection-check-IBT` to rmake.rs

- The Makefile version *never* ran because of Makefile syntax confusion because `ifeq ($(filter x86,$(LLVM_COMPONENTS)),x86_64)` [compares `x86` to `x86_64`, which always evaluates to false](rust-lang#126720 (comment)).
- The test would've always failed because precompiled std is not built with `-Z cf-protection=branch`, but linkers require all input object files to indicate IBT support in order to enable IBT for the executable, which is not the case for std.
- Thus, the test input file is instead changed to a `no_std` program.
- The test is currently limited to only `x86_64-unknown-linux-gnu` host, there are various other problems when the test is cross-compiled that I didn't want to fix atm, and is left as an exercise for the `-Z cf-protection` implementers.

The GNU property note was added by rust-lang#110304 in order to address rust-lang#103001.

Partially supersedes rust-lang#129156.
The rmake.rs port was initially authored by `@Rejyr` in rust-lang#126720.
This PR is co-authored with `@Oneirical` and `@Rejyr.`

r? `@bjorn3` or reroll

try-job: x86_64-mingw-1
try-job: x86_64-mingw-2
try-job: x86_64-msvc
try-job: x86_64-apple-1
try-job: x86_64-apple-2