Add ld_classic flag to Hermes when building for Xcode 15 (#39516)

Summary:
Pull Request resolved: #39516

With Xcode15, Apple rewrote the C++ linker.
This is a breaking change that does not work with weak symbols.
As a workaround, apple is suggesting to add `-ld_classic` to the linker in order to readd support for weak symbols. The flag does not exists for Xcode 14.3 or lower, so we need to add it conditionally.

With this change, we introduce a couple of checks in the Hermes build logic:
1. Detect the version of Xcode that is used
2. Add the new flag to `HERMES_EXTRA_LINKER_FLAGS` if Xcode version is 15.

[Internal] - Make hermes build properly with Xcode 15

Reviewed By: cortinico, dmytrorykun

Differential Revision: D49368675

fbshipit-source-id: 62d8ed81855c426f56ed94b6a2d6da2eb882b355

Author: cipolleschi

sdks/hermes-engine/utils/build-apple-framework.sh

@@ -52,7 +52,7 @@ function build_host_hermesc {
 
 # Utility function to configure an Apple framework
 function configure_apple_framework {
-  local build_cli_tools enable_bitcode enable_debugger cmake_build_type
+  local build_cli_tools enable_bitcode enable_debugger cmake_build_type xcode_15_flags xcode_major_version
 
   if [[ $1 == iphoneos || $1 == catalyst ]]; then
     enable_bitcode="true"
@@ -77,8 +77,15 @@ function configure_apple_framework {
     cmake_build_type="MinSizeRel"
   fi
 
+  xcode_15_flags=""
+  xcode_major_version=$(xcodebuild -version | grep -oE '[0-9]*' | head -n 1)
+  if [[ $xcode_major_version -ge 15 ]]; then
+    xcode_15_flags="LINKER:-ld_classic"
+  fi
+
   pushd "$HERMES_PATH" > /dev/null || exit 1
     cmake -S . -B "build_$1" \
+      -DHERMES_EXTRA_LINKER_FLAGS="$xcode_15_flags" \
       -DHERMES_APPLE_TARGET_PLATFORM:STRING="$1" \
       -DCMAKE_OSX_ARCHITECTURES:STRING="$2" \
       -DCMAKE_OSX_DEPLOYMENT_TARGET:STRING="$3" \

sdks/hermes-engine/utils/build-hermes-xcode.sh

@@ -33,13 +33,21 @@ if [ -z "$deployment_target" ]; then
   deployment_target=${MACOSX_DEPLOYMENT_TARGET}
 fi
 
+xcode_15_flags=""
+xcode_major_version=$(xcodebuild -version | grep -oE '[0-9]*' | head -n 1)
+if [[ $xcode_major_version -ge 15 ]]; then
+  echo "########### Using LINKER:-ld_classic ###########"
+  xcode_15_flags="LINKER:-ld_classic"
+fi
+
 architectures=$( echo "$ARCHS" | tr  " " ";" )
 
 echo "Configure Apple framework"
 
 "$CMAKE_BINARY" \
   -S "${PODS_ROOT}/hermes-engine" \
   -B "${PODS_ROOT}/hermes-engine/build/${PLATFORM_NAME}" \
+  -DHERMES_EXTRA_LINKER_FLAGS="$xcode_15_flags" \
   -DHERMES_APPLE_TARGET_PLATFORM:STRING="$PLATFORM_NAME" \
   -DCMAKE_OSX_ARCHITECTURES:STRING="$architectures" \
   -DCMAKE_OSX_DEPLOYMENT_TARGET:STRING="$deployment_target" \