[libc-commits] [libc] [libc] Make bigint trivially constructable (PR #206277)

[via libc-commits]

https://github.com/Sukumarsawant updated https://github.com/llvm/llvm-project/pull/206277

>From 1c07f07900f009398608b9d21ddd42aa26c2e304 Mon Sep 17 00:00:00 2001
From: Sukumarsawant <sawantsukumar at gmail.com>
Date: Sun, 28 Jun 2026 00:16:39 +0530
Subject: [PATCH 1/2] test for constexpr failures

---
 libc/src/__support/big_int.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libc/src/__support/big_int.h b/libc/src/__support/big_int.h
index 0e5c038ec356e..c1cf5b43fd1f5 100644
--- a/libc/src/__support/big_int.h
+++ b/libc/src/__support/big_int.h
@@ -358,7 +358,7 @@ struct BigInt {
 
   LIBC_INLINE_VAR static constexpr size_t WORD_COUNT = Bits / WORD_SIZE;
 
-  cpp::array<WordType, WORD_COUNT> val{}; // zero initialized.
+  cpp::array<WordType, WORD_COUNT> val; // zero initialized.
 
   LIBC_INLINE constexpr BigInt() = default;
 

>From 7aabfa421ef39741ef5a8edeab6b294b7c1ca397 Mon Sep 17 00:00:00 2001
From: Sukumarsawant <sawantsukumar at gmail.com>
Date: Sun, 28 Jun 2026 00:56:14 +0530
Subject: [PATCH 2/2] bigint changes

---
 libc/src/__support/big_int.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/libc/src/__support/big_int.h b/libc/src/__support/big_int.h
index c1cf5b43fd1f5..c71dfacf51608 100644
--- a/libc/src/__support/big_int.h
+++ b/libc/src/__support/big_int.h
@@ -366,7 +366,8 @@ struct BigInt {
 
   template <size_t OtherBits, bool OtherSigned, typename OtherWordType>
   LIBC_INLINE constexpr BigInt(
-      const BigInt<OtherBits, OtherSigned, OtherWordType> &other) {
+      const BigInt<OtherBits, OtherSigned, OtherWordType> &other)
+      : val{} {
     using BigIntOther = BigInt<OtherBits, OtherSigned, OtherWordType>;
     [[maybe_unused]] const bool should_sign_extend = Signed && other.is_neg();
 
@@ -491,7 +492,7 @@ struct BigInt {
   LIBC_INLINE static constexpr BigInt one() { return BigInt(1); }
   LIBC_INLINE static constexpr BigInt all_ones() { return ~zero(); }
   LIBC_INLINE static constexpr BigInt min() {
-    BigInt out;
+    BigInt out{};
     if constexpr (SIGNED)
       out.set_msb();
     return out;