dev-libs/gmp: tie --enable-fat to USE=cpudetection

Note that USE=-cpudetection still gives a very generic
build rather than one detected at build time to be
precisely the machine compiled on (for now?)

Bug: https://bugs.gentoo.org/883201
Signed-off-by: Sam James <sam@gentoo.org>

5 files changed, 28 insertions, 14 deletions

diff --git a/dev-libs/gmp/gmp-6.2.1-r3.ebuild b/dev-libs/gmp/gmp-6.2.1-r3.ebuild
index dc0cb7b4c773..8e7bca104d30 100644
--- a/dev-libs/gmp/gmp-6.2.1-r3.ebuild
+++ b/dev-libs/gmp/gmp-6.2.1-r3.ebuild
@@ -27,7 +27,8 @@ LICENSE="|| ( LGPL-3+ GPL-2+ )"
 SLOT="0/10.4"
 # Unkeyworded temporarily for some more testing
 #KEYWORDS="~alpha ~amd64 ~arm ~arm64 ~hppa ~ia64 ~loong ~m68k ~mips ~ppc ~ppc64 ~riscv ~s390 ~sparc ~x86 ~x64-cygwin ~amd64-linux ~x86-linux ~ppc-macos ~x64-macos ~sparc-solaris ~sparc64-solaris ~x64-solaris ~x86-solaris"
-IUSE="+asm doc +cxx pic static-libs"
+IUSE="+asm doc +cpudetection +cxx pic static-libs"
+REQUIRED_USE="cpudetection? ( asm )"
 
 BDEPEND="
 	app-arch/xz-utils
@@ -93,14 +94,14 @@ multilib_src_configure() {
 		--localstatedir="${EPREFIX}"/var/state/gmp
 		--enable-shared
 
+		$(use_enable asm assembly)
 		# fat is needed to avoid gmp installing either purely generic
 		# or specific-to-used-CPU (which our config.guess refresh prevents at the moment).
 		# Both Fedora and opensuse use this option to tackle the issue, bug #883201.
 		#
 		# This only works for x86, so we're still getting non-performant
 		# builds on other arches until we figure something out!
-		$(use_enable asm fat)
-		$(use_enable asm assembly)
+		$(use_enable cpudetection fat)
 		$(use_enable cxx)
 		$(use_enable static-libs static)
 
diff --git a/dev-libs/gmp/metadata.xml b/dev-libs/gmp/metadata.xml
index e98fbcba6811..753f212d3e39 100644
--- a/dev-libs/gmp/metadata.xml
+++ b/dev-libs/gmp/metadata.xml
@@ -1,15 +1,16 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE pkgmetadata SYSTEM "https://www.gentoo.org/dtd/metadata.dtd">
 <pkgmetadata>
-<maintainer type="project">
-	<email>toolchain@gentoo.org</email>
-	<name>Gentoo Toolchain Project</name>
-</maintainer>
-<use>
-	<flag name="asm">Enable use of hand optimized assembly routines (faster execution)</flag>
-	<flag name="pic">Force static libraries to be built as PIC to avoid TEXTRELs.</flag>
-</use>
-<upstream>
-	<remote-id type="cpe">cpe:/a:gmplib:gmp</remote-id>
-</upstream>
+	<maintainer type="project">
+		<email>toolchain@gentoo.org</email>
+		<name>Gentoo Toolchain Project</name>
+	</maintainer>
+	<use>
+		<flag name="asm">Enable use of hand optimized assembly routines (faster execution)</flag>
+		<flag name="cpudetection">Enables runtime CPU detection (useful for binpkgs, compatibility on other CPUs)</flag>
+		<flag name="pic">Force static libraries to be built as PIC to avoid TEXTRELs.</flag>
+	</use>
+	<upstream>
+		<remote-id type="cpe">cpe:/a:gmplib:gmp</remote-id>
+	</upstream>
 </pkgmetadata>
diff --git a/profiles/arch/amd64/package.use.mask b/profiles/arch/amd64/package.use.mask
index 27207c6da3f9..4fa0267b5a1b 100644
--- a/profiles/arch/amd64/package.use.mask
+++ b/profiles/arch/amd64/package.use.mask
@@ -17,6 +17,10 @@
 
 #--- END OF EXAMPLES ---
 
+# Sam James <sam@gentoo.org> (2022-11-30)
+# Only effective on amd64/x86.
+dev-libs/gmp -cpudetection
+
 # Guillermo Joandet <gjoandet@gmail.com> (2022-11-22)
 # app-text/pandoc is keyworded on this architecture
 net-libs/gssdp -man
diff --git a/profiles/arch/base/package.use.mask b/profiles/arch/base/package.use.mask
index 5a1455d90b27..a9a1bad325ca 100644
--- a/profiles/arch/base/package.use.mask
+++ b/profiles/arch/base/package.use.mask
@@ -1,6 +1,10 @@
 # Copyright 1999-2022 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
+# Sam James <sam@gentoo.org> (2022-11-30)
+# Only effective on amd64/x86.
+dev-libs/gmp cpudetection
+
 # Mike Gilbert <floppym@gentoo.org> (2022-10-16)
 # Only supported on MIPS.
 dev-lang/gnat-gpl fixed-point
diff --git a/profiles/arch/x86/package.use.mask b/profiles/arch/x86/package.use.mask
index a68e233ecfd9..20ce8131ba98 100644
--- a/profiles/arch/x86/package.use.mask
+++ b/profiles/arch/x86/package.use.mask
@@ -1,6 +1,10 @@
 # Copyright 1999-2022 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
+# Sam James <sam@gentoo.org> (2022-11-30)
+# Only effective on amd64/x86.
+dev-libs/gmp -cpudetection
+
 # Michał Górny <mgorny@gentoo.org> (2022-11-16)
 # spirv-llvm-translator is not keyworded x86.
 dev-libs/libclc spirv