diff --git a/src/codegen.cpp b/src/codegen.cpp
index 01a15b5f2c..1455b4b743 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -1425,7 +1425,12 @@ static void add_sentinel_check(CodeGen *g, LLVMValueRef sentinel_elem_ptr, ZigVa
     LLVMValueRef expected_sentinel = gen_const_val(g, sentinel, "");
 
     LLVMValueRef actual_sentinel = gen_load_untyped(g, sentinel_elem_ptr, 0, false, "");
-    LLVMValueRef ok_bit = LLVMBuildICmp(g->builder, LLVMIntEQ, actual_sentinel, expected_sentinel, "");
+    LLVMValueRef ok_bit;
+    if (sentinel->type->id == ZigTypeIdFloat) {
+        ok_bit = LLVMBuildFCmp(g->builder, LLVMRealOEQ, actual_sentinel, expected_sentinel, "");
+    } else {
+        ok_bit = LLVMBuildICmp(g->builder, LLVMIntEQ, actual_sentinel, expected_sentinel, "");
+    }
 
     LLVMBasicBlockRef fail_block = LLVMAppendBasicBlock(g->cur_fn_val, "SentinelFail");
     LLVMBasicBlockRef ok_block = LLVMAppendBasicBlock(g->cur_fn_val, "SentinelOk");
diff --git a/test/runtime_safety.zig b/test/runtime_safety.zig
index 6a1cc808fd..2217a7f2df 100644
--- a/test/runtime_safety.zig
+++ b/test/runtime_safety.zig
@@ -1,6 +1,34 @@
 const tests = @import("tests.zig");
 
 pub fn addCases(cases: *tests.CompareOutputContext) void {
+    cases.addRuntimeSafety("slice sentinel mismatch - optional pointers",
+        \\const std = @import("std");
+        \\pub fn panic(message: []const u8, stack_trace: ?*@import("builtin").StackTrace) noreturn {
+        \\    if (std.mem.eql(u8, message, "sentinel mismatch")) {
+        \\        std.process.exit(126); // good
+        \\    }
+        \\    std.process.exit(0); // test failed
+        \\}
+        \\pub fn main() void {
+        \\    var buf: [4]?*i32 = undefined;
+        \\    const slice = buf[0..3 :null];
+        \\}
+    );
+
+    cases.addRuntimeSafety("slice sentinel mismatch - floats",
+        \\const std = @import("std");
+        \\pub fn panic(message: []const u8, stack_trace: ?*@import("builtin").StackTrace) noreturn {
+        \\    if (std.mem.eql(u8, message, "sentinel mismatch")) {
+        \\        std.process.exit(126); // good
+        \\    }
+        \\    std.process.exit(0); // test failed
+        \\}
+        \\pub fn main() void {
+        \\    var buf: [4]f32 = undefined;
+        \\    const slice = buf[0..3 :1.2];
+        \\}
+    );
+
     cases.addRuntimeSafety("pointer slice sentinel mismatch",
         \\const std = @import("std");
         \\pub fn panic(message: []const u8, stack_trace: ?*@import("builtin").StackTrace) noreturn {