From 6f90d2c209ccf81498139133ee9ee4023eb176a6 Mon Sep 17 00:00:00 2001
From: Marc Tiehuis <marctiehuis@gmail.com>
Date: Fri, 22 Mar 2019 22:10:51 +1300
Subject: [PATCH 1/2] Fix bigint_append_buf

All current usages use base 10 and have a limb length of 1, hence why
we weren't hitting this error in practice.
---
 src/bigint.cpp | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/bigint.cpp b/src/bigint.cpp
index 4c103adce3..d3178c35c6 100644
--- a/src/bigint.cpp
+++ b/src/bigint.cpp
@@ -40,7 +40,7 @@ static uint8_t digit_to_char(uint8_t digit, bool uppercase) {
     if (digit <= 9) {
         return digit + '0';
     } else if (digit <= 35) {
-        return digit + (uppercase ? 'A' : 'a');
+        return (digit - 10) + (uppercase ? 'A' : 'a');
     } else {
         zig_unreachable();
     }
@@ -1545,6 +1545,10 @@ void bigint_append_buf(Buf *buf, const BigInt *op, uint64_t base) {
         buf_appendf(buf, "%" ZIG_PRI_u64, op->data.digit);
         return;
     }
+    if (op->digit_count == 1 && base == 16) {
+        buf_appendf(buf, "%" ZIG_PRI_x64, op->data.digit);
+        return;
+    }
     size_t first_digit_index = buf_len(buf);
 
     BigInt digit_bi = {0};
@@ -1556,7 +1560,7 @@ void bigint_append_buf(Buf *buf, const BigInt *op, uint64_t base) {
     bigint_init_bigint(a, op);
 
     BigInt base_bi = {0};
-    bigint_init_unsigned(&base_bi, 10);
+    bigint_init_unsigned(&base_bi, base);
 
     for (;;) {
         bigint_rem(&digit_bi, a, &base_bi);
@@ -1574,7 +1578,7 @@ void bigint_append_buf(Buf *buf, const BigInt *op, uint64_t base) {
     }
 
     // reverse
-    for (size_t i = first_digit_index; i < buf_len(buf); i += 1) {
+    for (size_t i = first_digit_index; i < buf_len(buf) / 2; i += 1) {
         size_t other_i = buf_len(buf) + first_digit_index - i - 1;
         uint8_t tmp = buf_ptr(buf)[i];
         buf_ptr(buf)[i] = buf_ptr(buf)[other_i];

From a3f42a5fe1bf483245e87d1084edd9ea21bce0f7 Mon Sep 17 00:00:00 2001
From: Marc Tiehuis <marctiehuis@gmail.com>
Date: Sat, 23 Mar 2019 00:17:26 +1300
Subject: [PATCH 2/2] Fix compile-error test case for large integer type

---
 test/compile_errors.zig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/compile_errors.zig b/test/compile_errors.zig
index 07970e490e..27a5432fdd 100644
--- a/test/compile_errors.zig
+++ b/test/compile_errors.zig
@@ -441,7 +441,7 @@ pub fn addCases(cases: *tests.CompileErrorContext) void {
         \\    var ptr: [*c]u8 = x;
         \\}
     ,
-        "tmp.zig:2:33: error: integer value 71615590737044764481 cannot be implicitly casted to type 'usize'",
+        "tmp.zig:2:33: error: integer value 18446744073709551617 cannot be implicitly casted to type 'usize'",
         "tmp.zig:6:23: error: integer type 'u65' too big for implicit @intToPtr to type '[*c]u8'",
     );