diff --git a/src/codegen/spirv.zig b/src/codegen/spirv.zig
index da2fa66feed941364ca2efc0900c0e28cd84abf1..67faf32471d7bbf879ab789edde9d01ea2c1f22f 100644
--- a/src/codegen/spirv.zig
+++ b/src/codegen/spirv.zig
@@ -629,7 +629,7 @@ pub const DeclGen = struct {
             const params = decl.ty.fnParamLen();
             var i: usize = 0;
 
-            try self.args.ensureTotalCapacity(params);
+            try self.args.ensureUnusedCapacity(params);
             while (i < params) : (i += 1) {
                 const param_type_id = self.spv.types.get(decl.ty.fnParamType(i)).?;
                 const arg_result_id = self.spv.allocResultId();
diff --git a/src/link/MachO/Dylib.zig b/src/link/MachO/Dylib.zig
index e3998a8548e03344167e50ce8d713ac4fa0d61f7..5b4ab6aa180289099340d6f427a68407737d7241 100644
--- a/src/link/MachO/Dylib.zig
+++ b/src/link/MachO/Dylib.zig
@@ -180,7 +180,7 @@ pub fn parse(self: *Dylib, allocator: *Allocator, target: std.Target) !void {
 fn readLoadCommands(self: *Dylib, allocator: *Allocator, reader: anytype) !void {
     const should_lookup_reexports = self.header.?.flags & macho.MH_NO_REEXPORTED_DYLIBS == 0;
 
-    try self.load_commands.ensureTotalCapacity(allocator, self.header.?.ncmds);
+    try self.load_commands.ensureUnusedCapacity(allocator, self.header.?.ncmds);
 
     var i: u16 = 0;
     while (i < self.header.?.ncmds) : (i += 1) {
diff --git a/src/link/MachO/Object.zig b/src/link/MachO/Object.zig
index f0a299182c6e89c87ffe8b8825f3fa65b160130f..21a0686fef6a7a57fdf30737b3cd82e6398cd71e 100644
--- a/src/link/MachO/Object.zig
+++ b/src/link/MachO/Object.zig
@@ -267,7 +267,7 @@ pub fn readLoadCommands(self: *Object, allocator: *Allocator, reader: anytype) !
     const header = self.header orelse unreachable; // Unreachable here signifies a fatal unexplored condition.
     const offset = self.file_offset orelse 0;
 
-    try self.load_commands.ensureTotalCapacity(allocator, header.ncmds);
+    try self.load_commands.ensureUnusedCapacity(allocator, header.ncmds);
 
     var i: u16 = 0;
     while (i < header.ncmds) : (i += 1) {