builder: implement float options

1 files changed, 20 insertions, 1 deletions

diff --git a/lib/std/build.zig b/lib/std/build.zig
index dacfaf5f75..8d6db459ea 100644
--- a/lib/std/build.zig
+++ b/lib/std/build.zig
@@ -509,7 +509,26 @@ pub const Builder = struct {
                     return null;
                 },
             },
-            .Float => panic("TODO float options to build script", .{}),
+            .Float => switch (entry.value.value) {
+                .Flag => {
+                    warn("Expected -D{} to be a float, but received a boolean.\n", .{name});
+                    self.markInvalidUserInput();
+                    return null;
+                },
+                .Scalar => |s| {
+                    const n = std.fmt.parseFloat(T, s) catch |err| {
+                        warn("Expected -D{} to be a float of type {}.\n", .{ name, @typeName(T) });
+                        self.markInvalidUserInput();
+                        return null;
+                    };
+                    return n;
+                },
+                .List => {
+                    warn("Expected -D{} to be a float, but received a list.\n", .{name});
+                    self.markInvalidUserInput();
+                    return null;
+                },
+            },
             .Enum => switch (entry.value.value) {
                 .Flag => {
                     warn("Expected -D{} to be a string, but received a boolean.\n", .{name});