diff --git a/std/crypto/md5.zig b/std/crypto/md5.zig
index a324e4b8c6..d1386d9be6 100644
--- a/std/crypto/md5.zig
+++ b/std/crypto/md5.zig
@@ -4,11 +4,11 @@ const endian = @import("../endian.zig");
 const debug = @import("../debug/index.zig");
 
 const RoundParam = struct {
-    a: u32, b: u32, c: u32, d: u32,
-    k: u32, s: u32, t: u32
+    a: usize, b: usize, c: usize, d: usize,
+    k: usize, s: u32, t: u32
 };
 
-fn Rp(a: u32, b: u32, c: u32, d: u32, k: u32, s: u5, t: u32) -> RoundParam {
+fn Rp(a: usize, b: usize, c: usize, d: usize, k: usize, s: u32, t: u32) -> RoundParam {
     return RoundParam { .a = a, .b = b, .c = c, .d = d, .k = k, .s = s, .t = t };
 }
 
diff --git a/std/crypto/sha1.zig b/std/crypto/sha1.zig
index 6a6d8ba3ee..5c8278700c 100644
--- a/std/crypto/sha1.zig
+++ b/std/crypto/sha1.zig
@@ -6,10 +6,10 @@ const debug = @import("../debug/index.zig");
 pub const u160 = @IntType(false, 160);
 
 const RoundParam = struct {
-    a: u32, b: u32, c: u32, d: u32, e: u32, i: u32,
+    a: usize, b: usize, c: usize, d: usize, e: usize, i: u32,
 };
 
-fn Rp(a: u32, b: u32, c: u32, d: u32, e: u32, i: u32) -> RoundParam {
+fn Rp(a: usize, b: usize, c: usize, d: usize, e: usize, i: u32) -> RoundParam {
     return RoundParam { .a = a, .b = b, .c = c, .d = d, .e = e, .i = i };
 }
 
diff --git a/std/crypto/sha2.zig b/std/crypto/sha2.zig
index 4fe46b551c..bc824bb3f3 100644
--- a/std/crypto/sha2.zig
+++ b/std/crypto/sha2.zig
@@ -7,11 +7,11 @@ const debug = @import("../debug/index.zig");
 // Sha224 + Sha256
 
 const RoundParam256 = struct {
-    a: u32, b: u32, c: u32, d: u32, e: u32, f: u32, g: u32, h: u32,
-    i: u32, k: u32,
+    a: usize, b: usize, c: usize, d: usize, e: usize, f: usize, g: usize, h: usize,
+    i: usize, k: u32,
 };
 
-fn Rp256(a: u32, b: u32, c: u32, d: u32, e: u32, f: u32, g: u32, h: u32, i: u32, k: u32) -> RoundParam256 {
+fn Rp256(a: usize, b: usize, c: usize, d: usize, e: usize, f: usize, g: usize, h: usize, i: usize, k: u32) -> RoundParam256 {
     return RoundParam256 { .a = a, .b = b, .c = c, .d = d, .e = e, .f = f, .g = g, .h = h, .i = i, .k = k };
 }
 
@@ -24,7 +24,7 @@ const Sha2Params32 = struct {
     iv5: u32,
     iv6: u32,
     iv7: u32,
-    out_len: u32,
+    out_len: usize,
 };
 
 const Sha224Params = Sha2Params32 {