Add MinGW build support.

SConstruct

@@ -230,11 +230,6 @@ for v in custom_build_steps:
     script_filename = cmd.split()[0]
     out_full_path = mesa_dir + "/generated/" + subdir
     out_file_full_path = out_full_path + "/" + gen_filename
-    env.Command(
-        out_file_full_path,
-        mesa_dir + "/" + subdir + "/" + script_filename,
-        ["cd " + in_dir + " && python " + (cmd % (out_dir))],
-    )
 
     if gen_filename.endswith(".h"):
         mesa_gen_include_paths += [out_full_path]
@@ -288,7 +283,6 @@ extra_defines += [
     ("PACKAGE_BUGREPORT", '\\"https://gitlab.freedesktop.org/mesa/mesa/-/issues\\"'),
     "PIPE_SUBSYSTEM_WINDOWS_USER",
     "_USE_MATH_DEFINES",
-    ("_Static_assert", "static_assert"),
 ]
 
 if env.get("is_msvc", False):
@@ -303,12 +297,14 @@ if env.get("is_msvc", False):
         ("_HAS_EXCEPTIONS", 0),
         "NOMINMAX",
         "HAVE_STRUCT_TIMESPEC",
+        ("_Static_assert", "static_assert"),
     ]
     env.Append(CFLAGS=["/std:c11"])
 else:
     env.Append(
         CPPDEFINES=[
             ("__MSVCRT_VERSION__", 0x0700),
+            "HAVE_STRUCT_TIMESPEC",
         ]
     )
     env.Append(CFLAGS=["-std=c11"])

update_mesa.sh

@@ -124,6 +124,7 @@ copy_sources() {
     # We still take the liberty to copy all the headers.
     copy_subir_headers src/util
     copy_file src/util blob.c
+    copy_file src/util bitscan.c
     copy_file src/util double.c
     copy_file src/util half_float.c
     copy_file src/util hash_table.c
@@ -165,11 +166,55 @@ tweak_gitignore() {
     check_error
 }
 
+custom_source_gen() {
+    run_step() {
+        local P_SUBDIR=$1
+        local P_SCRIPT_PLUS_ARGS=$2
+        local P_REDIR_TARGET=$3
+
+        echo "Custom step: [$P_SUBDIR] $P_SCRIPT_PLUS_ARGS"
+
+        local OUTDIR=$GODOT_DIR/godot-mesa/$P_SUBDIR
+        local GENDIR=$GODOT_DIR/godot-mesa/generated/$P_SUBDIR
+        mkdir -p $GENDIR
+        check_error
+        pushd $OUTDIR > /dev/null
+        check_error
+        eval "local COMMAND=\"$P_SCRIPT_PLUS_ARGS\""
+        if [ ! -z "$P_REDIR_TARGET" ]; then
+            eval "TARGET=\"$P_REDIR_TARGET\""
+            python3 $COMMAND > $GENDIR/$TARGET
+        else
+            python3 $COMMAND
+        fi
+        check_error
+        popd > /dev/null
+        check_error
+    }
+   
+    run_step 'src/compiler' 'glsl/ir_expression_operation.py enum' 'ir_expression_operation.h'
+    run_step 'src/compiler/nir' 'nir_builder_opcodes_h.py' 'nir_builder_opcodes.h'
+    run_step 'src/compiler/nir' 'nir_constant_expressions.py' 'nir_constant_expressions.c'
+    run_step 'src/compiler/nir' 'nir_intrinsics_h.py --outdir $GENDIR'
+    run_step 'src/compiler/nir' 'nir_intrinsics_c.py --outdir $GENDIR'
+    run_step 'src/compiler/nir' 'nir_intrinsics_indices_h.py --outdir $GENDIR'
+    run_step 'src/compiler/nir' 'nir_opcodes_h.py' 'nir_opcodes.h'
+    run_step 'src/compiler/nir' 'nir_opcodes_c.py' 'nir_opcodes.c'
+    run_step 'src/compiler/nir' 'nir_opt_algebraic.py' 'nir_opt_algebraic.c'
+    run_step 'src/compiler/spirv' 'vtn_generator_ids_h.py spir-v.xml $GENDIR/vtn_generator_ids.h'
+    run_step 'src/microsoft/compiler' 'dxil_nir_algebraic.py -p ../../../src/compiler/nir' 'dxil_nir_algebraic.c'
+    run_step 'src/util' 'format_srgb.py' 'format_srgb.c'
+    run_step 'src/util/format' 'u_format_table.py u_format.csv --header' 'u_format_pack.h'
+    run_step 'src/util/format' 'u_format_table.py u_format.csv' 'u_format_table.c'
+}
+
 
 GODOT_DIR=$(pwd)
 
-echo "Clearing godot-mesa/"
-find godot-mesa -mindepth 1 -type d | xargs rm -rf
+if [ -d ./godot-mesa ]; then
+    echo "Clearing godot-mesa/"
+    find godot-mesa -mindepth 1 -type d | xargs rm -rf
+fi
 
 run_custom_steps_at_source
 copy_custom_steps_sources
@@ -181,3 +226,5 @@ if [ -d ./godot-patches ]; then
     echo "Applying patches"
     find ./godot-patches -name '*.patch' -exec git apply {} \;
 fi
+
+custom_source_gen