1 files changed, 50 insertions, 0 deletions
diff --git a/thirdparty/fmt/doc/api.md b/thirdparty/fmt/doc/api.md
index 2c584abc0..9fbc9f2fe 100644
--- a/thirdparty/fmt/doc/api.md
+++ b/thirdparty/fmt/doc/api.md
@@ -708,3 +708,53 @@ following differences:
   `std::to_chars` which tries to generate the smallest number of characters
   (ignoring redundant digits and sign in exponent) and may procude more
   decimal digits than necessary.
+
+## Configuration Options
+
+{fmt} provides configuration via CMake options and preprocessor macros to
+enable or disable features and to optimize for binary size. For example, you
+can disable OS-specific APIs defined in `fmt/os.h` with `-DFMT_OS=OFF` when
+configuring CMake.
+
+### CMake Options
+
+- **`FMT_OS`**: When set to `OFF`, disables OS-specific APIs (`fmt/os.h`).
+- **`FMT_UNICODE`**: When set of `OFF`, disables Unicode support on
+  Windows/MSVC. Unicode support is always enabled on other platforms.
+
+### Macros
+
+- **`FMT_HEADER_ONLY`**: Enables the header-only mode when defined. It is an
+  alternative to using the `fmt::fmt-header-only` CMake target.
+  Default: not defined.
+
+- **`FMT_USE_EXCEPTIONS`**: Disables the use of exceptions when set to `0`.
+  Default: `1` (`0` if compiled with `-fno-exceptions`).
+
+- **`FMT_USE_LOCALE`**: When set to `0`, disables locale support.
+  Default: `1` (`0` when `FMT_OPTIMIZE_SIZE > 1`).
+
+- **`FMT_CUSTOM_ASSERT_FAIL`**: When set to `1`, allows users to provide a
+  custom `fmt::assert_fail` function which is called on assertion failures and,
+  if exceptions are disabled, on runtime errors. Default: `0`.
+
+- **`FMT_BUILTIN_TYPES`**: When set to `0`, disables built-in handling of
+  arithmetic and string types other than `int`. This reduces library size at
+  the cost of per-call overhead. Default: `1`.
+
+- **`FMT_OPTIMIZE_SIZE`**: Controls binary size optimizations:
+    - `0` - off (default)
+    - `1` - disables locale support and applies some optimizations
+    - `2` - disables some Unicode features, named arguments and applies more
+      aggresive optimizations
+
+### Binary Size Optimization
+
+To minimize the binary footprint of {fmt} as much as possible at the cost of
+some features, you can use the following configuration:
+
+- CMake options:
+    - `FMT_OS=OFF`
+- Macros:
+    - `FMT_BUILTIN_TYPES=0`
+    - `FMT_OPTIMIZE_SIZE=2`