Metal: Resolve zero initialization in failing math shader tests

Math tests failing in Metal due to non-zero-initialized values
and shader compilation error caused by mutli-component
boolean being implicitly evaluated.

Authored by Apple: Michael Parkin-White

Pull Request: https://projects.blender.org/blender/blender/pulls/108758

source/blender/gpu/shaders/common/gpu_shader_math_matrix_lib.glsl

@@ -650,11 +650,11 @@ mat4x4 normalize_and_get_size(mat4x4 mat, out vec4 r_size)
 
 mat2x2 adjoint(mat2x2 mat)
 {
-  mat2x2 adj;
+  mat2x2 adj = mat2x2(0.0);
   for (int c = 0; c < 2; c++) {
     for (int r = 0; r < 2; r++) {
       /* Copy other cells except the "cross" to compute the determinant. */
-      float tmp;
+      float tmp = 0.0;
       for (int m_c = 0; m_c < 2; m_c++) {
         for (int m_r = 0; m_r < 2; m_r++) {
           if (m_c != c && m_r != r) {
@@ -671,11 +671,11 @@ mat2x2 adjoint(mat2x2 mat)
 }
 mat3x3 adjoint(mat3x3 mat)
 {
-  mat3x3 adj;
+  mat3x3 adj = mat3x3(0.0);
   for (int c = 0; c < 3; c++) {
     for (int r = 0; r < 3; r++) {
       /* Copy other cells except the "cross" to compute the determinant. */
-      mat2x2 tmp;
+      mat2x2 tmp = mat2x2(0.0);
       for (int m_c = 0; m_c < 3; m_c++) {
         for (int m_r = 0; m_r < 3; m_r++) {
           if (m_c != c && m_r != r) {
@@ -694,11 +694,11 @@ mat3x3 adjoint(mat3x3 mat)
 }
 mat4x4 adjoint(mat4x4 mat)
 {
-  mat4x4 adj;
+  mat4x4 adj = mat4x4(0.0);
   for (int c = 0; c < 4; c++) {
     for (int r = 0; r < 4; r++) {
       /* Copy other cells except the "cross" to compute the determinant. */
-      mat3x3 tmp;
+      mat3x3 tmp = mat3x3(0.0);
       for (int m_c = 0; m_c < 4; m_c++) {
         for (int m_r = 0; m_r < 4; m_r++) {
           if (m_c != c && m_r != r) {

source/blender/gpu/shaders/common/gpu_shader_test_lib.glsl

@@ -146,7 +146,7 @@ int g_test_id = 0;
 
 #  define EXPECT_OP(OP, val1, val2) \
     out_test[g_test_id++] = test_output( \
-        as_raw_data(val1), as_raw_data(val2), bool(OP), int(__LINE__), to_type(val1))
+        as_raw_data(val1), as_raw_data(val2), bool(all(OP)), int(__LINE__), to_type(val1))
 #else
 
 /** WORKAROUND: Fragment shader variant for older platform. */
@@ -158,7 +158,7 @@ int g_test_id = 0;
     } \
     if (int(gl_FragCoord.y) == g_test_id - 1) { \
       TestOutput to = test_output( \
-          as_raw_data(val1), as_raw_data(val2), bool(OP), int(__LINE__), to_type(val1)); \
+          as_raw_data(val1), as_raw_data(val2), bool(all(OP)), int(__LINE__), to_type(val1)); \
       switch (int(gl_FragCoord.x)) { \
         case 0: \
           out_test = uvec4( \