langref: runtime_shrExact_overflow does not work as expected on RISC-V

#24304

Author: alexrp

doc/langref/runtime_shrExact_overflow.zig

@@ -1,10 +1,13 @@
+const builtin = @import("builtin");
 const std = @import("std");
 
 pub fn main() void {
     var x: u8 = 0b10101010; // runtime-known
     _ = &x;
     const y = @shrExact(x, 2);
     std.debug.print("value: {}\n", .{y});
+
+    if (builtin.cpu.arch.isRISCV() and builtin.zig_backend == .stage2_llvm) @panic("https://github.com/ziglang/zig/issues/24304");
 }
 
 // exe=fail