| Message ID | 20241011114040.3900487-1-gary@garyguo.net (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | kbuild: rust: add `CONFIG_RUSTC_LLVM_VERSION` | expand |
On Fri, Oct 11, 2024 at 1:41 PM Gary Guo <gary@garyguo.net> wrote: > > The invocation of rustc-version is being moved from init/Kconfig to > scripts/Kconfig.include for consistency with cc-version. Yeah, I am ambivalent. Dropping them would minimize changes and avoid introducing something only used once, which would be nice too. Happy either way. > +if output=$("$@" --version --verbose 2>/dev/null | grep LLVM); then Similarly, I wonder if we should use '^LLVM version: ' here or similar to minimize the chances the "LLVM" string appears elsewhere in the future (perhaps in a custom string a vendor adds, though I would expect them to add it lowercase). We are relying on having a $3 when splitting anyway. Depending on what Masahiro prefers, I will take this one or the one-invocation-only one. Thanks Gary! Cheers, Miguel
On Fri, 11 Oct 2024 13:53:47 +0200 Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> wrote: > On Fri, Oct 11, 2024 at 1:41 PM Gary Guo <gary@garyguo.net> wrote: > > > > The invocation of rustc-version is being moved from init/Kconfig to > > scripts/Kconfig.include for consistency with cc-version. > > Yeah, I am ambivalent. Dropping them would minimize changes and avoid > introducing something only used once, which would be nice too. Happy > either way. > Another motivation is that in my helper inline series, I need to do arithmetic on LLVM version (divide it by 10000 to get major verison), which isn't possible for config options, but will work for variables defiend in Kconfig.include. I didn't mention it in the commit message for this patch because this is not my patch series :) Best, Gary > > +if output=$("$@" --version --verbose 2>/dev/null | grep LLVM); then > > Similarly, I wonder if we should use '^LLVM version: ' here or similar > to minimize the chances the "LLVM" string appears elsewhere in the > future (perhaps in a custom string a vendor adds, though I would > expect them to add it lowercase). We are relying on having a $3 when > splitting anyway. > > Depending on what Masahiro prefers, I will take this one or the > one-invocation-only one. > > Thanks Gary! > > Cheers, > Miguel
On Fri, Oct 11, 2024 at 9:06 PM Gary Guo <gary@garyguo.net> wrote: > > On Fri, 11 Oct 2024 13:53:47 +0200 > Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> wrote: > > > On Fri, Oct 11, 2024 at 1:41 PM Gary Guo <gary@garyguo.net> wrote: > > > > > > The invocation of rustc-version is being moved from init/Kconfig to > > > scripts/Kconfig.include for consistency with cc-version. > > > > Yeah, I am ambivalent. Dropping them would minimize changes and avoid > > introducing something only used once, which would be nice too. Happy > > either way. > > Another motivation is that in my helper inline series, I need to do > arithmetic on LLVM version (divide it by 10000 to get major verison), > which isn't possible for config options, but will work for variables > defiend in Kconfig.include. > > I didn't mention it in the commit message for this patch because this > is not my patch series :) I tend to agree with Muguel. The motivation of having cc-version in scripts/Kconfig.include is to check the presence of the supported C compiler, as C compiler is mandatory (in contrast, Rust compiler is optional). If you have a reason to have it in scripts/Kconfig.include for your future works, it is OK with me, but I cannot judge it. > > Best, > Gary > > > > +if output=$("$@" --version --verbose 2>/dev/null | grep LLVM); then > > > > Similarly, I wonder if we should use '^LLVM version: ' here or similar > > to minimize the chances the "LLVM" string appears elsewhere in the > > future (perhaps in a custom string a vendor adds, though I would > > expect them to add it lowercase). We are relying on having a $3 when > > splitting anyway. > > > > Depending on what Masahiro prefers, I will take this one or the > > one-invocation-only one. > > > > Thanks Gary! > > > > Cheers, > > Miguel > >
On Mon, Oct 14, 2024 at 6:27 PM Masahiro Yamada <masahiroy@kernel.org> wrote: > > I tend to agree with Muguel. > The motivation of having cc-version in scripts/Kconfig.include > is to check the presence of the supported C compiler, as C compiler > is mandatory (in contrast, Rust compiler is optional). > > If you have a reason to have it in scripts/Kconfig.include > for your future works, it is OK with me, but I cannot judge it. Thanks Masahiro -- OK, since it seems Gary needs it, and we already have the patch here, I will take that one. Cheers, Miguel
On Fri, Oct 11, 2024 at 1:41 PM Gary Guo <gary@garyguo.net> wrote: > > Each version of Rust supports a range of LLVM versions. There are cases where > we want to gate a config on the LLVM version instead of the Rust version. > Normalized cfi integer tags are one example [1]. > > The invocation of rustc-version is being moved from init/Kconfig to > scripts/Kconfig.include for consistency with cc-version. > > Link: https://lore.kernel.org/all/20240925-cfi-norm-kasan-fix-v1-1-0328985cdf33@google.com/ [1] > Signed-off-by: Gary Guo <gary@garyguo.net> Applied to `rust-fixes` -- thanks everyone! [ Added missing `-llvm` to the Usage documentation. - Miguel ] Cheers, Miguel
diff --git a/init/Kconfig b/init/Kconfig index fbd0cb06a50a..304e2bd32bfd 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -62,7 +62,7 @@ config LLD_VERSION config RUSTC_VERSION int - default $(shell,$(srctree)/scripts/rustc-version.sh $(RUSTC)) + default $(rustc-version) help It does not depend on `RUST` since that one may need to use the version in a `depends on`. @@ -78,6 +78,10 @@ config RUST_IS_AVAILABLE In particular, the Makefile target 'rustavailable' is useful to check why the Rust toolchain is not being detected. +config RUSTC_LLVM_VERSION + int + default $(rustc-llvm-version) + config CC_CAN_LINK bool default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) $(USERCFLAGS) $(USERLDFLAGS) $(m64-flag)) if 64BIT diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include index 785a491e5996..33193ca6e803 100644 --- a/scripts/Kconfig.include +++ b/scripts/Kconfig.include @@ -65,6 +65,9 @@ cc-option-bit = $(if-success,$(CC) -Werror $(1) -E -x c /dev/null -o /dev/null,$ m32-flag := $(cc-option-bit,-m32) m64-flag := $(cc-option-bit,-m64) +rustc-version := $(shell,$(srctree)/scripts/rustc-version.sh $(RUSTC)) +rustc-llvm-version := $(shell,$(srctree)/scripts/rustc-llvm-version.sh $(RUSTC)) + # $(rustc-option,<flag>) # Return y if the Rust compiler supports <flag>, n otherwise # Calls to this should be guarded so that they are not evaluated if diff --git a/scripts/rustc-llvm-version.sh b/scripts/rustc-llvm-version.sh new file mode 100755 index 000000000000..b8ffa24afea8 --- /dev/null +++ b/scripts/rustc-llvm-version.sh @@ -0,0 +1,22 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# +# Usage: $ ./rustc-version.sh rustc +# +# Print the LLVM version that the Rust compiler uses in a 6 digit form. + +# Convert the version string x.y.z to a canonical up-to-6-digits form. +get_canonical_version() +{ + IFS=. + set -- $1 + echo $((10000 * $1 + 100 * $2 + $3)) +} + +if output=$("$@" --version --verbose 2>/dev/null | grep LLVM); then + set -- $output + get_canonical_version $3 +else + echo 0 + exit 1 +fi
Each version of Rust supports a range of LLVM versions. There are cases where we want to gate a config on the LLVM version instead of the Rust version. Normalized cfi integer tags are one example [1]. The invocation of rustc-version is being moved from init/Kconfig to scripts/Kconfig.include for consistency with cc-version. Link: https://lore.kernel.org/all/20240925-cfi-norm-kasan-fix-v1-1-0328985cdf33@google.com/ [1] Signed-off-by: Gary Guo <gary@garyguo.net> --- init/Kconfig | 6 +++++- scripts/Kconfig.include | 3 +++ scripts/rustc-llvm-version.sh | 22 ++++++++++++++++++++++ 3 files changed, 30 insertions(+), 1 deletion(-) create mode 100755 scripts/rustc-llvm-version.sh base-commit: f5e50614e39e74401b492a2fa125f2e2b6458bab