fix: Build on stock apple clang. (#592)

bootstrap.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+(cd cpp && ./bootstrap.sh)
+cd ts
+yarn build
+npm link

cpp/bootstrap.sh

@@ -32,19 +32,7 @@ cd ..
 # Pick native toolchain file.
 ARCH=$(uname -m)
 if [ "$OS" == "macos" ]; then
-  if [ "$(which brew)" != "" ]; then
-    export BREW_PREFIX=$(brew --prefix)
-
-    # Ensure we have toolchain.
-    if [ ! "$?" -eq 0 ] || [ ! -f "$BREW_PREFIX/opt/llvm/bin/clang++" ]; then
-      echo "Default clang not sufficient. Install homebrew, and then: brew install llvm libomp clang-format"
-      exit 1
-    fi
-
-    PRESET=homebrew
-  else
-    PRESET=default
-  fi
+  PRESET=default
 else
   if [ "$(which clang++-15)" != "" ]; then
     PRESET=clang15

cpp/src/barretenberg/polynomials/polynomial.hpp

@@ -199,6 +199,13 @@ template <typename Fr> class Polynomial {
     void factor_roots(std::span<const Fr> roots) { polynomial_arithmetic::factor_roots(std::span{ *this }, roots); };
     void factor_roots(const Fr& root) { polynomial_arithmetic::factor_roots(std::span{ *this }, root); };
 
+#ifdef __clang__
+    // Needed for clang versions earlier than 14.0.3, but breaks gcc.
+    // Can remove once ecosystem is firmly upgraded.
+    operator std::span<Fr>() { return std::span<Fr>(coefficients_.get(), size_); }
+    operator std::span<const Fr>() const { return std::span<const Fr>(coefficients_.get(), size_); }
+#endif
+
     iterator begin() { return coefficients_.get(); }
     iterator end() { return coefficients_.get() + size_; }
     pointer data() { return coefficients_; }

cpp/src/barretenberg/proof_system/polynomial_store/polynomial_store.test.cpp

@@ -90,25 +90,4 @@ TEST(PolynomialStore, Remove)
     EXPECT_EQ(polynomial_store.get_size_in_bytes(), bytes_expected);
 }
 
-// Check that PolynomialStore supports range based for loop
-TEST(PolynomialStore, RangeBasedFor)
-{
-    PolynomialStore<Fr> polynomial_store;
-    size_t size = 100;
-    Polynomial poly1(size);
-    Polynomial poly2(size);
-
-    polynomial_store.put("id_1", std::move(poly1));
-    polynomial_store.put("id_2", std::move(poly2));
-
-    // Check that PolynomialStore meets criteria for std::ranges::range
-    EXPECT_TRUE(std::ranges::range<PolynomialStore<Fr>>);
-
-    // For example ...
-    // Polynomial polynomial_sum(size);
-    // for (const auto& [key, polynomial] : polynomial_store) {
-    //     polynomial_sum += polynomial;
-    // }
-}
-
 } // namespace proof_system