diff --git a/programs/vkd3d-compiler/main.c b/programs/vkd3d-compiler/main.c
index 2a2c6b96..2289bfba 100644
--- a/programs/vkd3d-compiler/main.c
+++ b/programs/vkd3d-compiler/main.c
@@ -191,8 +191,9 @@ static void print_usage(const char *program_name)
         "  --formatting=<flags>  Specify the formatting options for text output.\n"
         "                        <flags> is a comma separated list of formatting flags,\n"
         "                        optionally prefixed by '+' or '-'. Valid flags are\n"
-        "                        'colour', 'indent', 'offsets', 'header', and 'raw-ids'.\n"
-        "                        The 'indent' and 'header' flags are enabled by default.\n"
+        "                        'colour', 'indent', 'offsets', 'header', 'raw-ids',\n"
+        "                        and 'signatures'. The 'indent' and 'header' flags are\n"
+        "                        enabled by default.\n"
         "  --fragment-coordinate-origin=<origin>\n"
         "                        Specify the origin of fragment coordinates for SPIR-V\n"
         "                        targets. Valid values are 'upper-left' (default) and\n"
@@ -300,11 +301,12 @@ static bool parse_formatting(uint32_t *formatting, bool *colour, char *arg)
     }
     opts[] =
     {
-        {"colour",  VKD3D_SHADER_COMPILE_OPTION_FORMATTING_COLOUR},
-        {"indent",  VKD3D_SHADER_COMPILE_OPTION_FORMATTING_INDENT},
-        {"offsets", VKD3D_SHADER_COMPILE_OPTION_FORMATTING_OFFSETS},
-        {"header",  VKD3D_SHADER_COMPILE_OPTION_FORMATTING_HEADER},
-        {"raw-ids", VKD3D_SHADER_COMPILE_OPTION_FORMATTING_RAW_IDS},
+        {"colour",     VKD3D_SHADER_COMPILE_OPTION_FORMATTING_COLOUR},
+        {"indent",     VKD3D_SHADER_COMPILE_OPTION_FORMATTING_INDENT},
+        {"offsets",    VKD3D_SHADER_COMPILE_OPTION_FORMATTING_OFFSETS},
+        {"header",     VKD3D_SHADER_COMPILE_OPTION_FORMATTING_HEADER},
+        {"raw-ids",    VKD3D_SHADER_COMPILE_OPTION_FORMATTING_RAW_IDS},
+        {"signatures", VKD3D_SHADER_COMPILE_OPTION_FORMATTING_IO_SIGNATURES},
     };
     char *tok;