From 32972a59249931f79ea5c7d551ec65a4ca1c173c Mon Sep 17 00:00:00 2001
From: xnorai <147757538+xnorai@users.noreply.github.com>
Date: Thu, 24 Oct 2024 08:54:51 -0700
Subject: [PATCH] C++20 compatibility for fmt (#1519)

* C++20 compatibility for fmt

* Address review feedback

* Remove stray string

* Add newlines back
---
 mlx/backend/metal/indexing.cpp    | 2 +-
 mlx/backend/metal/jit_kernels.cpp | 5 +++--
 mlx/backend/metal/kernels.h       | 8 ++++----
 3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/mlx/backend/metal/indexing.cpp b/mlx/backend/metal/indexing.cpp
index 37c511b39..7820b0272 100644
--- a/mlx/backend/metal/indexing.cpp
+++ b/mlx/backend/metal/indexing.cpp
@@ -262,7 +262,7 @@ void Scatter::eval_gpu(const std::vector<array>& inputs, array& out) {
         break;
     }
     if (reduce_type_ != Scatter::None) {
-      op_type = fmt::format(op_type, out_type_str);
+      op_type = fmt::format(fmt::runtime(op_type), out_type_str);
     }
     auto [idx_args, idx_arr] = make_index_args(idx_type_str, nidx);
 
diff --git a/mlx/backend/metal/jit_kernels.cpp b/mlx/backend/metal/jit_kernels.cpp
index 430ff65af..ff567f0c0 100644
--- a/mlx/backend/metal/jit_kernels.cpp
+++ b/mlx/backend/metal/jit_kernels.cpp
@@ -445,8 +445,9 @@ MTL::ComputePipelineState* get_steel_gemm_splitk_accum_kernel(
     kernel_source << metal::utils() << metal::gemm()
                   << metal::steel_gemm_splitk()
                   << fmt::format(
-                         axbpy ? steel_gemm_splitk_accum_axbpy_kernels
-                               : steel_gemm_splitk_accum_kernels,
+                         fmt::runtime(
+                             axbpy ? steel_gemm_splitk_accum_axbpy_kernels
+                                   : steel_gemm_splitk_accum_kernels),
                          "name"_a = lib_name,
                          "atype"_a = get_type_string(in.dtype()),
                          "otype"_a = get_type_string(out.dtype()));
diff --git a/mlx/backend/metal/kernels.h b/mlx/backend/metal/kernels.h
index 2f861373d..d8a258cb8 100644
--- a/mlx/backend/metal/kernels.h
+++ b/mlx/backend/metal/kernels.h
@@ -209,10 +209,10 @@ get_template_definition(std::string name, std::string func, Args... args) {
   };
   (add_arg(args), ...);
   s << ">";
-  std::string base_string = R"(
-template [[host_name("{0}")]] [[kernel]] decltype({1}) {1};
-  )";
-  return fmt::format(base_string, name, s.str());
+  return fmt::format(
+      "\ntemplate [[host_name(\"{0}\")]] [[kernel]] decltype({1}) {1};\n",
+      name,
+      s.str());
 }
 
 } // namespace mlx::core