disable failing CBE behavior tests failing on aarch64-windows

Also start to move redundant tests next to each other to make them
slightly more obvious that they need to be cleaned up.

See tracking issue #13876

6 files changed, 343 insertions, 260 deletions

diff --git a/test/behavior/align.zig b/test/behavior/align.zig
index b536ffc6aa..780ee06875 100644
--- a/test/behavior/align.zig
+++ b/test/behavior/align.zig
@@ -275,10 +275,20 @@ test "page aligned array on stack" {
     if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-    // https://github.com/ziglang/zig/issues/13679
+
     if (builtin.zig_backend == .stage2_llvm and
-        builtin.cpu.arch == .aarch64 and
-        builtin.os.tag == .windows) return error.SkipZigTest;
+        builtin.cpu.arch == .aarch64 and builtin.os.tag == .windows)
+    {
+        // https://github.com/ziglang/zig/issues/13679
+        return error.SkipZigTest;
+    }
+
+    if (builtin.zig_backend == .stage2_c and
+        builtin.os.tag == .windows and builtin.cpu.arch == .aarch64)
+    {
+        // https://github.com/ziglang/zig/issues/13876
+        return error.SkipZigTest;
+    }
 
     // Large alignment value to make it hard to accidentally pass.
     var array align(0x1000) = [_]u8{ 1, 2, 3, 4, 5, 6, 7, 8 };
diff --git a/test/behavior/cast.zig b/test/behavior/cast.zig
index 894138edf4..1822922ec2 100644
--- a/test/behavior/cast.zig
+++ b/test/behavior/cast.zig
@@ -1351,6 +1351,13 @@ test "cast f128 to narrower types" {
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
 
+    if (builtin.os.tag == .windows and builtin.cpu.arch == .aarch64 and
+        builtin.zig_backend == .stage2_c)
+    {
+        // https://github.com/ziglang/zig/issues/13876
+        return error.SkipZigTest;
+    }
+
     const S = struct {
         fn doTheTest() !void {
             var x: f128 = 1234.0;
diff --git a/test/behavior/floatop.zig b/test/behavior/floatop.zig
index ed3ff983b3..7befa41380 100644
--- a/test/behavior/floatop.zig
+++ b/test/behavior/floatop.zig
@@ -185,6 +185,32 @@ test "more @sqrt f16 tests" {
     try expect(math.isNan(@sqrt(@as(f16, math.nan(f16)))));
 }
 
+test "another, possibly redundant @sqrt test" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+
+    try testSqrtLegacy(f64, 12.0);
+    comptime try testSqrtLegacy(f64, 12.0);
+    try testSqrtLegacy(f32, 13.0);
+    comptime try testSqrtLegacy(f32, 13.0);
+    try testSqrtLegacy(f16, 13.0);
+    comptime try testSqrtLegacy(f16, 13.0);
+
+    // TODO: make this pass
+    if (false) {
+        const x = 14.0;
+        const y = x * x;
+        const z = @sqrt(y);
+        comptime try expect(z == x);
+    }
+}
+
+fn testSqrtLegacy(comptime T: type, x: T) !void {
+    try expect(@sqrt(x * x) == x);
+}
+
 test "@sin" {
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
@@ -529,6 +555,85 @@ fn testFabsWithVectors() !void {
     try expect(math.approxEqAbs(f32, @fabs(@as(f32, -0.4)), result[3], epsilon));
 }
 
+test "another, possibly redundant, @fabs test" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+
+    if (builtin.os.tag == .windows and builtin.cpu.arch == .aarch64 and
+        builtin.zig_backend == .stage2_c)
+    {
+        // https://github.com/ziglang/zig/issues/13876
+        return error.SkipZigTest;
+    }
+
+    try testFabsLegacy(f128, 12.0);
+    comptime try testFabsLegacy(f128, 12.0);
+    try testFabsLegacy(f64, 12.0);
+    comptime try testFabsLegacy(f64, 12.0);
+    try testFabsLegacy(f32, 12.0);
+    comptime try testFabsLegacy(f32, 12.0);
+    try testFabsLegacy(f16, 12.0);
+    comptime try testFabsLegacy(f16, 12.0);
+
+    const x = 14.0;
+    const y = -x;
+    const z = @fabs(y);
+    comptime try std.testing.expectEqual(x, z);
+}
+
+test "@fabs f80" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+
+    try testFabsLegacy(f80, 12.0);
+    comptime try testFabsLegacy(f80, 12.0);
+}
+
+fn testFabsLegacy(comptime T: type, x: T) !void {
+    const y = -x;
+    const z = @fabs(y);
+    try expect(x == z);
+}
+
+test "a third @fabs test, surely there should not be three fabs tests" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+
+    if (builtin.os.tag == .windows and builtin.cpu.arch == .aarch64 and
+        builtin.zig_backend == .stage2_c)
+    {
+        // https://github.com/ziglang/zig/issues/13876
+        return error.SkipZigTest;
+    }
+
+    inline for ([_]type{ f16, f32, f64, f80, f128, c_longdouble }) |T| {
+        // normals
+        try expect(@fabs(@as(T, 1.0)) == 1.0);
+        try expect(@fabs(@as(T, -1.0)) == 1.0);
+        try expect(@fabs(math.floatMin(T)) == math.floatMin(T));
+        try expect(@fabs(-math.floatMin(T)) == math.floatMin(T));
+        try expect(@fabs(math.floatMax(T)) == math.floatMax(T));
+        try expect(@fabs(-math.floatMax(T)) == math.floatMax(T));
+
+        // subnormals
+        try expect(@fabs(@as(T, 0.0)) == 0.0);
+        try expect(@fabs(@as(T, -0.0)) == 0.0);
+        try expect(@fabs(math.floatTrueMin(T)) == math.floatTrueMin(T));
+        try expect(@fabs(-math.floatTrueMin(T)) == math.floatTrueMin(T));
+
+        // non-finite numbers
+        try expect(math.isPositiveInf(@fabs(math.inf(T))));
+        try expect(math.isPositiveInf(@fabs(-math.inf(T))));
+        try expect(math.isNan(@fabs(math.nan(T))));
+    }
+}
+
 test "@floor" {
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
@@ -573,6 +678,56 @@ fn testFloorWithVectors() !void {
     try expect(math.approxEqAbs(f32, @floor(@as(f32, -0.4)), result[3], epsilon));
 }
 
+test "another, possibly redundant, @floor test" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+
+    try testFloorLegacy(f64, 12.0);
+    comptime try testFloorLegacy(f64, 12.0);
+    try testFloorLegacy(f32, 12.0);
+    comptime try testFloorLegacy(f32, 12.0);
+    try testFloorLegacy(f16, 12.0);
+    comptime try testFloorLegacy(f16, 12.0);
+
+    const x = 14.0;
+    const y = x + 0.7;
+    const z = @floor(y);
+    comptime try expect(x == z);
+}
+
+test "@floor f80" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+
+    if (builtin.zig_backend == .stage2_llvm and builtin.os.tag == .windows) {
+        // https://github.com/ziglang/zig/issues/12602
+        return error.SkipZigTest;
+    }
+
+    try testFloorLegacy(f80, 12.0);
+    comptime try testFloorLegacy(f80, 12.0);
+}
+
+test "@floor f128" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+
+    try testFloorLegacy(f128, 12.0);
+    comptime try testFloorLegacy(f128, 12.0);
+}
+
+fn testFloorLegacy(comptime T: type, x: T) !void {
+    const y = x + 0.6;
+    const z = @floor(y);
+    try expect(x == z);
+}
+
 test "@ceil" {
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
@@ -617,6 +772,56 @@ fn testCeilWithVectors() !void {
     try expect(math.approxEqAbs(f32, @ceil(@as(f32, -0.4)), result[3], epsilon));
 }
 
+test "another, possibly redundant, @ceil test" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+
+    try testCeilLegacy(f64, 12.0);
+    comptime try testCeilLegacy(f64, 12.0);
+    try testCeilLegacy(f32, 12.0);
+    comptime try testCeilLegacy(f32, 12.0);
+    try testCeilLegacy(f16, 12.0);
+    comptime try testCeilLegacy(f16, 12.0);
+
+    const x = 14.0;
+    const y = x - 0.7;
+    const z = @ceil(y);
+    comptime try expect(x == z);
+}
+
+test "@ceil f80" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+
+    if (builtin.zig_backend == .stage2_llvm and builtin.os.tag == .windows) {
+        // https://github.com/ziglang/zig/issues/12602
+        return error.SkipZigTest;
+    }
+
+    try testCeilLegacy(f80, 12.0);
+    comptime try testCeilLegacy(f80, 12.0);
+}
+
+test "@ceil f128" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+
+    try testCeilLegacy(f128, 12.0);
+    comptime try testCeilLegacy(f128, 12.0);
+}
+
+fn testCeilLegacy(comptime T: type, x: T) !void {
+    const y = x - 0.8;
+    const z = @ceil(y);
+    try expect(x == z);
+}
+
 test "@trunc" {
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
@@ -661,6 +866,70 @@ fn testTruncWithVectors() !void {
     try expect(math.approxEqAbs(f32, @trunc(@as(f32, -0.4)), result[3], epsilon));
 }
 
+test "another, possibly redundant, @trunc test" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+
+    try testTruncLegacy(f64, 12.0);
+    comptime try testTruncLegacy(f64, 12.0);
+    try testTruncLegacy(f32, 12.0);
+    comptime try testTruncLegacy(f32, 12.0);
+    try testTruncLegacy(f16, 12.0);
+    comptime try testTruncLegacy(f16, 12.0);
+
+    const x = 14.0;
+    const y = x + 0.7;
+    const z = @trunc(y);
+    comptime try expect(x == z);
+}
+
+test "@trunc f80" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+
+    if (builtin.zig_backend == .stage2_llvm and builtin.os.tag == .windows) {
+        // https://github.com/ziglang/zig/issues/12602
+        return error.SkipZigTest;
+    }
+
+    try testTruncLegacy(f80, 12.0);
+    comptime try testTruncLegacy(f80, 12.0);
+    comptime {
+        const x: f80 = 12.0;
+        const y = x + 0.8;
+        const z = @trunc(y);
+        try expect(x == z);
+    }
+}
+
+test "@trunc f128" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+
+    try testTruncLegacy(f128, 12.0);
+    comptime try testTruncLegacy(f128, 12.0);
+}
+
+fn testTruncLegacy(comptime T: type, x: T) !void {
+    {
+        const y = x + 0.8;
+        const z = @trunc(y);
+        try expect(x == z);
+    }
+
+    {
+        const y = -x - 0.8;
+        const z = @trunc(y);
+        try expect(-x == z);
+    }
+}
+
 test "negation f16" {
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
@@ -757,6 +1026,13 @@ test "negation f128" {
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
 
+    if (builtin.os.tag == .windows and builtin.cpu.arch == .aarch64 and
+        builtin.zig_backend == .stage2_c)
+    {
+        // https://github.com/ziglang/zig/issues/13876
+        return error.SkipZigTest;
+    }
+
     const S = struct {
         fn doTheTest() !void {
             var a: f128 = 1;
diff --git a/test/behavior/math.zig b/test/behavior/math.zig
index 88cc373adb..d352457bbb 100644
--- a/test/behavior/math.zig
+++ b/test/behavior/math.zig
@@ -578,6 +578,13 @@ test "f128" {
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
 
+    if (builtin.os.tag == .windows and builtin.cpu.arch == .aarch64 and
+        builtin.zig_backend == .stage2_c)
+    {
+        // https://github.com/ziglang/zig/issues/13876
+        return error.SkipZigTest;
+    }
+
     try test_f128();
     comptime try test_f128();
 }
@@ -1150,7 +1157,18 @@ test "remainder division" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_llvm and builtin.os.tag == .windows) return error.SkipZigTest; // https://github.com/ziglang/zig/issues/12602
+
+    if (builtin.zig_backend == .stage2_llvm and builtin.os.tag == .windows) {
+        // https://github.com/ziglang/zig/issues/12602
+        return error.SkipZigTest;
+    }
+
+    if (builtin.zig_backend == .stage2_c and builtin.os.tag == .windows and
+        builtin.cpu.arch == .aarch64)
+    {
+        // https://github.com/ziglang/zig/issues/13876
+        return error.SkipZigTest;
+    }
 
     comptime try remdiv(f16);
     comptime try remdiv(f32);
@@ -1262,233 +1280,6 @@ fn fmodOne(comptime T: type, a: T, b: T, c: T, epsilon: T) !void {
     try expect(@fabs(@mod(@as(T, a), @as(T, b)) - @as(T, c)) < epsilon);
 }
 
-test "@sqrt" {
-    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-
-    try testSqrt(f64, 12.0);
-    comptime try testSqrt(f64, 12.0);
-    try testSqrt(f32, 13.0);
-    comptime try testSqrt(f32, 13.0);
-    try testSqrt(f16, 13.0);
-    comptime try testSqrt(f16, 13.0);
-
-    // TODO: make this pass
-    if (false) {
-        const x = 14.0;
-        const y = x * x;
-        const z = @sqrt(y);
-        comptime try expect(z == x);
-    }
-}
-
-fn testSqrt(comptime T: type, x: T) !void {
-    try expect(@sqrt(x * x) == x);
-}
-
-test "@fabs" {
-    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-
-    try testFabs(f128, 12.0);
-    comptime try testFabs(f128, 12.0);
-    try testFabs(f64, 12.0);
-    comptime try testFabs(f64, 12.0);
-    try testFabs(f32, 12.0);
-    comptime try testFabs(f32, 12.0);
-    try testFabs(f16, 12.0);
-    comptime try testFabs(f16, 12.0);
-
-    const x = 14.0;
-    const y = -x;
-    const z = @fabs(y);
-    comptime try expectEqual(x, z);
-}
-
-test "@fabs f80" {
-    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-
-    try testFabs(f80, 12.0);
-    comptime try testFabs(f80, 12.0);
-}
-
-fn testFabs(comptime T: type, x: T) !void {
-    const y = -x;
-    const z = @fabs(y);
-    try expect(x == z);
-}
-
-test "@floor" {
-    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-
-    try testFloor(f64, 12.0);
-    comptime try testFloor(f64, 12.0);
-    try testFloor(f32, 12.0);
-    comptime try testFloor(f32, 12.0);
-    try testFloor(f16, 12.0);
-    comptime try testFloor(f16, 12.0);
-
-    const x = 14.0;
-    const y = x + 0.7;
-    const z = @floor(y);
-    comptime try expect(x == z);
-}
-
-test "@floor f80" {
-    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_llvm and builtin.os.tag == .windows) return error.SkipZigTest; // https://github.com/ziglang/zig/issues/12602
-
-    try testFloor(f80, 12.0);
-    comptime try testFloor(f80, 12.0);
-}
-
-test "@floor f128" {
-    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-
-    try testFloor(f128, 12.0);
-    comptime try testFloor(f128, 12.0);
-}
-
-fn testFloor(comptime T: type, x: T) !void {
-    const y = x + 0.6;
-    const z = @floor(y);
-    try expect(x == z);
-}
-
-test "@ceil" {
-    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-
-    try testCeil(f64, 12.0);
-    comptime try testCeil(f64, 12.0);
-    try testCeil(f32, 12.0);
-    comptime try testCeil(f32, 12.0);
-    try testCeil(f16, 12.0);
-    comptime try testCeil(f16, 12.0);
-
-    const x = 14.0;
-    const y = x - 0.7;
-    const z = @ceil(y);
-    comptime try expect(x == z);
-}
-
-test "@ceil f80" {
-    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_llvm and builtin.os.tag == .windows) return error.SkipZigTest; // https://github.com/ziglang/zig/issues/12602
-
-    try testCeil(f80, 12.0);
-    comptime try testCeil(f80, 12.0);
-}
-
-test "@ceil f128" {
-    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-
-    try testCeil(f128, 12.0);
-    comptime try testCeil(f128, 12.0);
-}
-
-fn testCeil(comptime T: type, x: T) !void {
-    const y = x - 0.8;
-    const z = @ceil(y);
-    try expect(x == z);
-}
-
-test "@trunc" {
-    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-
-    try testTrunc(f64, 12.0);
-    comptime try testTrunc(f64, 12.0);
-    try testTrunc(f32, 12.0);
-    comptime try testTrunc(f32, 12.0);
-    try testTrunc(f16, 12.0);
-    comptime try testTrunc(f16, 12.0);
-
-    const x = 14.0;
-    const y = x + 0.7;
-    const z = @trunc(y);
-    comptime try expect(x == z);
-}
-
-test "@trunc f80" {
-    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_llvm and builtin.os.tag == .windows) return error.SkipZigTest; // https://github.com/ziglang/zig/issues/12602
-
-    try testTrunc(f80, 12.0);
-    comptime try testTrunc(f80, 12.0);
-    comptime {
-        const x: f80 = 12.0;
-        const y = x + 0.8;
-        const z = @trunc(y);
-        try expect(x == z);
-    }
-}
-
-test "@trunc f128" {
-    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-
-    try testTrunc(f128, 12.0);
-    comptime try testTrunc(f128, 12.0);
-}
-
-fn testTrunc(comptime T: type, x: T) !void {
-    {
-        const y = x + 0.8;
-        const z = @trunc(y);
-        try expect(x == z);
-    }
-
-    {
-        const y = -x - 0.8;
-        const z = @trunc(y);
-        try expect(-x == z);
-    }
-}
-
 test "@round" {
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
@@ -1567,6 +1358,13 @@ test "NaN comparison" {
     if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
 
+    if (builtin.zig_backend == .stage2_c and builtin.os.tag == .windows and
+        builtin.cpu.arch == .aarch64)
+    {
+        // https://github.com/ziglang/zig/issues/13876
+        return error.SkipZigTest;
+    }
+
     try testNanEqNan(f16);
     try testNanEqNan(f32);
     try testNanEqNan(f64);
@@ -1667,35 +1465,6 @@ test "comptime sin and ln" {
     try expect(v == @sin(@as(f32, 1)) + @log(@as(f32, 5)));
 }
 
-test "fabs" {
-    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
-    if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
-
-    inline for ([_]type{ f16, f32, f64, f80, f128, c_longdouble }) |T| {
-        // normals
-        try expect(@fabs(@as(T, 1.0)) == 1.0);
-        try expect(@fabs(@as(T, -1.0)) == 1.0);
-        try expect(@fabs(math.floatMin(T)) == math.floatMin(T));
-        try expect(@fabs(-math.floatMin(T)) == math.floatMin(T));
-        try expect(@fabs(math.floatMax(T)) == math.floatMax(T));
-        try expect(@fabs(-math.floatMax(T)) == math.floatMax(T));
-
-        // subnormals
-        try expect(@fabs(@as(T, 0.0)) == 0.0);
-        try expect(@fabs(@as(T, -0.0)) == 0.0);
-        try expect(@fabs(math.floatTrueMin(T)) == math.floatTrueMin(T));
-        try expect(@fabs(-math.floatTrueMin(T)) == math.floatTrueMin(T));
-
-        // non-finite numbers
-        try expect(math.isPositiveInf(@fabs(math.inf(T))));
-        try expect(math.isPositiveInf(@fabs(-math.inf(T))));
-        try expect(math.isNan(@fabs(math.nan(T))));
-    }
-}
-
 test "absFloat" {
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
diff --git a/test/behavior/muladd.zig b/test/behavior/muladd.zig
index 16f7e551a8..da00355b35 100644
--- a/test/behavior/muladd.zig
+++ b/test/behavior/muladd.zig
@@ -70,6 +70,13 @@ test "@mulAdd f128" {
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
 
+    if (builtin.os.tag == .windows and builtin.cpu.arch == .aarch64 and
+        builtin.zig_backend == .stage2_c)
+    {
+        // https://github.com/ziglang/zig/issues/13876
+        return error.SkipZigTest;
+    }
+
     comptime try testMulAdd128();
     try testMulAdd128();
 }
diff --git a/test/behavior/widening.zig b/test/behavior/widening.zig
index ff38df382b..ddd438d5d3 100644
--- a/test/behavior/widening.zig
+++ b/test/behavior/widening.zig
@@ -44,6 +44,13 @@ test "float widening" {
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
 
+    if (builtin.os.tag == .windows and builtin.cpu.arch == .aarch64 and
+        builtin.zig_backend == .stage2_c)
+    {
+        // https://github.com/ziglang/zig/issues/13876
+        return error.SkipZigTest;
+    }
+
     var a: f16 = 12.34;
     var b: f32 = a;
     var c: f64 = b;
@@ -64,6 +71,13 @@ test "float widening f16 to f128" {
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
 
+    if (builtin.os.tag == .windows and builtin.cpu.arch == .aarch64 and
+        builtin.zig_backend == .stage2_c)
+    {
+        // https://github.com/ziglang/zig/issues/13876
+        return error.SkipZigTest;
+    }
+
     var x: f16 = 12.34;
     var y: f128 = x;
     try expect(x == y);