build: fix range-loop-analysis warnings

iterator/zip.hpp

@@ -66,7 +66,7 @@ namespace cruft::iterator {
             zipped_iterator operator++ (int);
 
 
-            auto
+            decltype(auto)
             operator* (void)
             {
                 // We deliberately construct a tuple manually here to reduce

term.cpp

@@ -91,7 +91,7 @@ cruft::term::has_csi_support (void)
 
 ///////////////////////////////////////////////////////////////////////////////
 graphics::graphics (layer _layer, hue _hue):
-    m_value (_layer + _hue)
+    m_value (_layer + int (_hue))
 { ; }
 
 

test/expected.cpp

@@ -8,8 +8,15 @@ int main ()
 {
     cruft::TAP::logger tap;
 
-    tap.expect_nothrow ([] () { cruft::expected<std::string,int> { "foo" }; }, "value construction succeeds");
-    tap.expect_nothrow ([] () { cruft::expected<std::string,int> { EPERM }; }, "error construction succeeds");
+    tap.expect_nothrow (
+        [] () { (void)cruft::expected<std::string,int> { "foo" }; },
+        "value construction succeeds"
+    );
+
+    tap.expect_nothrow (
+        [] () { (void)cruft::expected<std::string,int> { EPERM }; },
+        "error construction succeeds"
+    );
 
     tap.expect_eq (cruft::expected<std::string,int> { "foo" }.value (), "foo", "value matches");
     tap.expect_eq (cruft::expected<std::string,int> { EPERM }.error (), EPERM, "error matches");

test/geom/segment.cpp

@@ -106,7 +106,7 @@ void test_bresenham (cruft::TAP::logger &tap)
 
     for (auto const &t: TESTS) {
         std::vector<cruft::point2i> computed;
-        for (auto const &p: cruft::geom::bresenham ({ t.a, t.b }))
+        for (auto const p: cruft::geom::bresenham ({ t.a, t.b }))
             computed.push_back (p);
         tap.expect_eq (computed, t.expected, "bresenham: %!", t.message);
     }

test/iterator.cpp

@@ -65,7 +65,7 @@ main (int, char**)
         char c_char[] = { '\0', 'b', 'c' };
 
         bool success = true;
-        for (auto const &[i, v, a, c]: cruft::iterator::izip (v_int, a_float, c_char)) {
+        for (auto const [i, v, a, c]: cruft::iterator::izip (v_int, a_float, c_char)) {
             success = success &&
                       v_int[i] == v &&
                       cruft::equal (a_float[i], a) &&

test/string.cpp

@@ -25,7 +25,7 @@ test_transforms (cruft::TAP::logger &tap)
         { "Don't.", "DON'T.", "don't.", "upper and lower and symbols" },
     };
 
-    for (auto const [src, upper, lower, msg]: TESTS) {
+    for (auto const &[src, upper, lower, msg]: TESTS) {
         tap.expect_eq (cruft::to_upper (src), upper, "to_upper, %!", msg);
         tap.expect_eq (cruft::to_lower (src), lower, "to_lower, %!", msg);
     }