Fix linux build

Package.swift

@@ -3,6 +3,12 @@
 import PackageDescription
 import CompilerPluginSupport
 
+#if canImport(simd)
+let simdAvailable = true
+#else
+let simdAvailable = false
+#endif
+
 let package = Package(
     name: "simd-tools",
     platforms: [
@@ -20,7 +26,9 @@ let package = Package(
     ],
     dependencies: [
         .package(url: "https://github.com/apple/swift-syntax.git", .upToNextMajor(from: "600.0.1")),
-    ],
+    ] + (simdAvailable ? [] : [
+        .package(url: "https://github.com/keyvariable/kvSIMD.swift.git", from: "1.1.0"),
+    ]),
     targets: [
         .macro(
             name: "SIMDToolsMacros",
@@ -29,7 +37,12 @@ let package = Package(
                 .product(name: "SwiftCompilerPlugin", package: "swift-syntax")
             ]
         ),
-        .target(name: "SIMDTools", dependencies: ["SIMDToolsMacros"]),
+        .target(
+            name: "SIMDTools",
+            dependencies: ["SIMDToolsMacros"] + (simdAvailable ? [] : [
+                .product(name: "kvSIMD", package: "kvSIMD.swift"),
+            ])
+        ),
         .testTarget(
             name: "SIMDToolsTests",
             dependencies: ["SIMDTools"]

Sources/SIMDTools/Angle.swift

@@ -1,4 +1,8 @@
 import simd
+#if !canImport(Darwin)
+// If we don't have Apple-specific intrinsics, use Glibc instead
+import Glibc
+#endif
 
 /// A floating point value that represents an angle
 
@@ -11,6 +15,11 @@ public struct Angle {
     public var radians: Float32 {
         degrees * Float32.pi / 180.0
     }
+
+    @inline(__always)
+    public var piFactor: Float {
+        degrees / 180.0
+    }
 
     /// Creates an instance using the value in radians
     /// - Parameter radians: The angle value in radians
@@ -208,7 +217,13 @@ extension Angle: Comparable {
 ///   - sina: A reference to a variable to store the sine of the angle
 ///   - cosa: A reference to a variable to store the cosine of the angle
 public func sincos(_ a: Angle, _ sina: inout Float, _ cosa: inout Float)  {
-    __sincospif(a.degrees / 180.0, &sina, &cosa)
+    #if canImport(Darwin)
+    __sincospif(a.piFactor, &sina, &cosa)
+    #else
+    let r = a.radians
+    sina = sinf(r)
+    cosa = cosf(r)
+    #endif
 }
 
 /// Computes the sine and cosine of the given angle
@@ -218,27 +233,38 @@ public func sincos(_ a: Angle) -> (sin: Float, cos: Float) {
     var s: Float = 0.0
     var c: Float = 0.0
     sincos(a, &s, &c)
-
     return (sin: s, cos: c)
 }
 
 /// Computes the sine of the given angle
 /// - Parameter a: The angle
 /// - Returns: The sine of the angle
 public func sin(_ a: Angle) -> Float {
-    __sinpif(a.degrees / 180.0)
+    #if canImport(Darwin)
+    return __sinpif(a.piFactor)
+    #else
+    return sinf(a.radians)
+    #endif
 }
 
 /// Computes the cosine of the given angle
 /// - Parameter a: The angle
 /// - Returns: The cosine of the angle
 public func cos(_ a: Angle) -> Float {
-    __cospif(a.degrees / 180.0)
+    #if canImport(Darwin)
+    return __cospif(a.piFactor)
+    #else
+    return cosf(a.radians)
+    #endif
 }
 
 /// Computes the tangent of the given angle
 /// - Parameter a: The angle
 /// - Returns: The tangent of the angle
 public func tan(_ a: Angle) -> Float {
-    __tanpif(a.degrees / 180.0)
+    #if canImport(Darwin)
+    return __tanpif(a.piFactor)
+    #else
+    return tanf(a.radians)
+    #endif
 }

Sources/SIMDToolsMacros/SIMDToolsMacro.swift

@@ -2,6 +2,7 @@ import SwiftCompilerPlugin
 import SwiftSyntax
 import SwiftSyntaxBuilder
 import SwiftSyntaxMacros
+import Foundation
 
 enum MacroExpansionError: Error, CustomStringConvertible {
     case invalidArguments