Rollup merge of #124741 - nebulark:patchable-function-entries-pr, r=estebank,workingjubilee

patchable-function-entry: Add unstable compiler flag and attribute

Tracking issue: #123115

Add the -Z patchable-function-entry compiler flag and the #[patchable_function_entry(prefix_nops = m, entry_nops = n)] attribute.
Rebased and adjusted the canditate implementation to match changes in the RFC.

1 files changed, 17 insertions, 0 deletions

diff --git a/tests/ui/patchable-function-entry/patchable-function-entry-attribute.rs b/tests/ui/patchable-function-entry/patchable-function-entry-attribute.rs
new file mode 100644
index 00000000000..1e376c9ff3c
--- /dev/null
+++ b/tests/ui/patchable-function-entry/patchable-function-entry-attribute.rs
@@ -0,0 +1,17 @@
+#![feature(patchable_function_entry)]
+fn main() {}
+
+#[patchable_function_entry(prefix_nops = 256, entry_nops = 0)]//~error: integer value out of range
+pub fn too_high_pnops() {}
+
+#[patchable_function_entry(prefix_nops = "stringvalue", entry_nops = 0)]//~error: invalid literal value
+pub fn non_int_nop() {}
+
+#[patchable_function_entry]//~error: malformed `patchable_function_entry` attribute input
+pub fn malformed_attribute() {}
+
+#[patchable_function_entry(prefix_nops = 10, something = 0)]//~error: unexpected parameter name
+pub fn unexpected_parameter_name() {}
+
+#[patchable_function_entry()]//~error: must specify at least one parameter
+pub fn no_parameters_given() {}