profiles: mask dev-lang/rust[mrustc-bootstrap]; unmask on ~amd64

Signed-off-by: Matt Jolly <kangie@gentoo.org>

profiles/arch/amd64/package.use.mask

@@ -17,11 +17,15 @@
 
 #--- END OF EXAMPLES ---
 
+# Matt Jolly <kangie@gentoo.org> (2025-01-11)
+# We can bootstrap with mrustc on amd64.
+dev-lang/rust -mrustc-bootstrap
+
 # Michał Górny <mgorny@gentoo.org> (2024-12-24)
 # OpenMP offloading is supported on 64-bit architectures only.
 llvm-core/clang-runtime -offload
 
-# Alfred Wingate <parona@protonmail.com> <2024-12-16)
+# Alfred Wingate <parona@protonmail.com> (2024-12-16)
 # Only available on amd64.
 media-video/handbrake -qsv
 

profiles/arch/amd64/package.use.stable.mask

@@ -17,6 +17,10 @@
 
 #--- END OF EXAMPLES ---
 
+# Matt Jolly <kangie@gentoo.org> (2025-01-11)
+# Stable-mask until mrustc is stabilised
+dev-lang/rust mrustc-bootstrap
+
 # Ionen Wolkens <ionen@gentoo.org> (2024-09-27)
 # dev-qt/qtremoteobjects:6 has not been stabilized yet.
 dev-python/pyqt6 remoteobjects

profiles/base/package.use.mask

@@ -3,6 +3,10 @@
 
 # New entries go on top.
 
+# Matt Jolly <kangie@gentoo.org> (2025-01-11)
+# mrustc currenly only works on amd64.
+dev-lang/rust mrustc-bootstrap
+
 # Volkmar W. Pogatzki <gentoo@pogatzki.net> (2025-01-09)
 # No suitable versions of dev-libs/protobuf available.
 =dev-java/protobuf-java-4.29.3 system-protoc