Link dynamically against libclang
diff -rupN a/c2rust/Cargo.toml b/c2rust/Cargo.toml
--- a/c2rust/Cargo.toml	2024-01-06 22:49:13.145706727 +0100
+++ b/c2rust/Cargo.toml	2024-01-06 22:49:56.895188304 +0100
@@ -31,7 +31,3 @@ time-macros = "=0.2.6"
 
 [build-dependencies]
 c2rust-build-paths = { path = "../c2rust-build-paths", version = "0.18.0" }
-
-[features]
-# Force static linking of LLVM
-llvm-static = ["c2rust-transpile/llvm-static"]
diff -rupN a/c2rust-ast-exporter/Cargo.toml b/c2rust-ast-exporter/Cargo.toml
--- a/c2rust-ast-exporter/Cargo.toml	2024-01-06 22:49:13.132373552 +0100
+++ b/c2rust-ast-exporter/Cargo.toml	2024-01-06 22:50:53.591183135 +0100
@@ -24,8 +24,3 @@ clang-sys = "1.3"
 cmake = "0.1.49"
 env_logger = "0.10"
 c2rust-build-paths = { path = "../c2rust-build-paths", version = "0.18.0" }
-
-[features]
-default = []
-# Force static linking of LLVM
-llvm-static = []
diff -rupN a/c2rust-ast-exporter/build.rs b/c2rust-ast-exporter/build.rs
--- a/c2rust-ast-exporter/build.rs	2024-01-06 22:49:13.132373552 +0100
+++ b/c2rust-ast-exporter/build.rs	2024-01-06 22:49:18.425644161 +0100
@@ -147,55 +147,7 @@ fn build_native(llvm_info: &LLVMInfo) {
 
     println!("cargo:rustc-link-search=native={}", llvm_lib_dir);
 
-    // Some distro's, including arch and Fedora, no longer build with
-    // BUILD_SHARED_LIBS=ON; programs linking to clang are required to
-    // link to libclang-cpp.so instead of individual libraries.
-    let use_libclang = if cfg!(target_os = "macos") {
-        // We hit an issue linking against the shared libraries for the homebrew
-        // version of LLVM 15 because they use a feature (opaque pointers) which
-        // are not understood by earlier versions of LLVM so we link against
-        // libclang unless static linking has been explicitly requested.
-        !cfg!(feature = "llvm-static")
-    } else {
-        // target_os = "linux"
-        let mut libclang_path = PathBuf::new();
-        libclang_path.push(llvm_lib_dir);
-        libclang_path.push("libclang-cpp.so");
-        libclang_path.exists()
-    };
-
-    if use_libclang {
-        println!("cargo:rustc-link-lib=clang-cpp");
-    } else {
-        // Link against these Clang libs. The ordering here is important! Libraries
-        // must be listed before their dependencies when statically linking.
-        let mut clang_libs = vec![
-            "clangTooling",
-            "clangFrontend",
-            "clangASTMatchers",
-            "clangParse",
-            "clangSerialization",
-            "clangSema",
-            "clangEdit",
-            "clangAnalysis",
-            "clangDriver",
-            "clangFormat",
-            "clangToolingCore",
-            "clangAST",
-            "clangRewrite",
-            "clangLex",
-            "clangBasic",
-        ];
-        if llvm_info.llvm_major_version >= 15 {
-            // insert after clangSema
-            let sema_pos = clang_libs.iter().position(|&r| r == "clangSema").unwrap();
-            clang_libs.insert(sema_pos + 1, "clangSupport");
-        }
-
-        for lib in &clang_libs {
-            println!("cargo:rustc-link-lib={}", lib);
-        }
-    }
+    println!("cargo:rustc-link-lib=clang-cpp");
 
     for lib in &llvm_info.libs {
         // IMPORTANT: We cannot specify static= or dylib= here because rustc
diff -rupN a/c2rust-ast-exporter/src/CMakeLists.txt b/c2rust-ast-exporter/src/CMakeLists.txt
--- a/c2rust-ast-exporter/src/CMakeLists.txt	2024-01-06 22:49:13.132373552 +0100
+++ b/c2rust-ast-exporter/src/CMakeLists.txt	2024-01-06 22:49:18.425644161 +0100
@@ -95,11 +95,7 @@ set_target_properties(c2rust-ast-exporte
 # PRIVATE was added to make c2rust-ast-exporter build with LLVM 6.0. Keyword
 # description: https://cmake.org/pipermail/cmake/2016-May/063400.html
 target_link_libraries(c2rust-ast-exporter PRIVATE
-  clangAST
-  clangFrontend
-  clangTooling
-  clangBasic
-  clangASTMatchers
+  clang-cpp
   tinycbor
   )
 
diff -rupN a/c2rust-ast-exporter/src/CMakeLists.txt.orig b/c2rust-ast-exporter/src/CMakeLists.txt.orig
--- a/c2rust-ast-exporter/src/CMakeLists.txt.orig	1970-01-01 01:00:00.000000000 +0100
+++ b/c2rust-ast-exporter/src/CMakeLists.txt.orig	2023-05-22 22:14:35.000000000 +0200
@@ -0,0 +1,117 @@
+cmake_minimum_required(VERSION 3.4.3)
+project(ASTExporter)
+
+#################################################
+# TinyCBOR                                      #
+#################################################
+
+set(TINYCBOR_REPO "https://github.com/intel/tinycbor.git" CACHE STRING "tinycbor git repo URL")
+
+# v0.6.3 tag, but using the commit hash instead (of the tarball hash) for integrity checks
+# unlike a .tar.gz MD5 hash, this SHA-1 commit hash should stay stable regardless of compression/archiving
+# (GitHub has changed this), and still retains the integrity check
+set(TINYCBOR_TAG "d393c16f3eb30d0c47e6f9d92db62272f0ec4dc7" CACHE STRING "tinycbor git tag/branch/commit hash")
+
+set(TINYCBOR_PREFIX "${CMAKE_BINARY_DIR}/tinycbor" CACHE STRING "tinycbor install prefix")
+
+if(CMAKE_SYSTEM_NAME STREQUAL "FreeBSD")
+    set(MAKE "gmake")
+else()
+    set(MAKE "make")
+endif()
+
+include(ExternalProject)
+ExternalProject_Add(tinycbor_build
+            PREFIX ${TINYCBOR_PREFIX}
+            INSTALL_DIR ${CMAKE_BINARY_DIR}
+            GIT_REPOSITORY ${TINYCBOR_REPO}
+            GIT_TAG ${TINYCBOR_TAG}
+            # the fd redirection here fails when the build run inside Cargo.
+            # patch from upstream:
+            # https://github.com/intel/tinycbor/commit/6176e0a28d7c5ef3a5e9cbd02521999c412de72c
+            PATCH_COMMAND patch --forward -p1 < ${CMAKE_CURRENT_SOURCE_DIR}/tinycbor_fix_build.patch || true
+            CONFIGURE_COMMAND ${MAKE} .config && cat ${CMAKE_CURRENT_SOURCE_DIR}/tinycbor.config >> .config
+            BUILD_COMMAND ${MAKE} --quiet prefix=<INSTALL_DIR> CFLAGS=-fPIC
+            INSTALL_COMMAND ${MAKE} --quiet prefix=<INSTALL_DIR> install
+            BUILD_IN_SOURCE 1
+            BUILD_BYPRODUCTS ${CMAKE_BINARY_DIR}/lib/libtinycbor.a
+)
+
+include_directories(${CMAKE_BINARY_DIR}/include)
+
+add_library(tinycbor STATIC IMPORTED)
+set_target_properties(tinycbor PROPERTIES IMPORTED_LOCATION ${CMAKE_BINARY_DIR}/lib/libtinycbor.a)
+add_dependencies(tinycbor tinycbor_build)
+
+set(AST_EXPORTER_SRCS
+  AstExporter.cpp
+  FloatingLexer.cpp
+  ExportResult.cpp
+  )
+
+set(AST_EXPORTER_BIN_SRCS
+  ${AST_EXPORTER_SRCS}
+  Main.cpp
+  )
+
+find_package(LLVM REQUIRED CONFIG)
+
+# Debian and Ubuntu's clang cmake files are broken, so we can't require the
+# package here. We already have to manually order the link against the clang
+# libs in build.rs, so that's not so bad.
+find_package(Clang CONFIG)
+
+include_directories(${LLVM_INCLUDE_DIRS} ${CLANG_INCLUDE_DIRS})
+add_definitions(${LLVM_DEFINITIONS} ${CLANG_DEFINITIONS})
+
+if (DEFINED CLANG_INSTALL_PREFIX)
+  add_definitions(-DCLANG_BIN_PATH="${CLANG_INSTALL_PREFIX}/bin")
+elseif(DEFINED LLVM_INSTALL_PREFIX)
+  add_definitions(-DCLANG_BIN_PATH="${LLVM_INSTALL_PREFIX}/bin")
+elseif(DEFINED LLVM_TOOLS_BINARY_DIR)
+  add_definitions(-DCLANG_BIN_PATH="${LLVM_TOOLS_BINARY_DIR}")
+else()
+  message(FATAL_ERROR "Cannot find path to clang binary")
+endif()
+add_definitions(-DCLANG_VERSION_STRING="${LLVM_PACKAGE_VERSION}")
+
+set(LLVM_LINK_COMPONENTS support)
+
+# LLVM is not always built with RTTI, we don't need it either.
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-rtti")
+
+# The executable
+add_executable(c2rust-ast-exporter ${AST_EXPORTER_BIN_SRCS})
+
+# The library
+add_library(clangAstExporter STATIC ${AST_EXPORTER_SRCS})
+
+add_definitions(-DCLANG_LIBDIR_SUFFIX="${LLVM_LIBDIR_SUFFIX}")
+
+set_target_properties(c2rust-ast-exporter PROPERTIES
+  CXX_STANDARD 14
+  CXX_EXTENSIONS OFF
+  )
+# PRIVATE was added to make c2rust-ast-exporter build with LLVM 6.0. Keyword
+# description: https://cmake.org/pipermail/cmake/2016-May/063400.html
+target_link_libraries(c2rust-ast-exporter PRIVATE
+  clangAST
+  clangFrontend
+  clangTooling
+  clangBasic
+  clangASTMatchers
+  tinycbor
+  )
+
+set_target_properties(clangAstExporter PROPERTIES
+  CXX_STANDARD 17 # will decay to 14 if compiler doesn't support c++17
+  CXX_EXTENSIONS OFF
+  )
+target_link_libraries(clangAstExporter PRIVATE
+  clangAST
+  clangFrontend
+  clangTooling
+  clangBasic
+  clangASTMatchers
+  tinycbor
+  )
diff -rupN a/c2rust-transpile/Cargo.toml b/c2rust-transpile/Cargo.toml
--- a/c2rust-transpile/Cargo.toml	2024-01-06 22:49:13.145706727 +0100
+++ b/c2rust-transpile/Cargo.toml	2024-01-06 22:49:18.425644161 +0100
@@ -38,7 +38,3 @@ smallvec = "1.0"
 strum = "0.24"
 strum_macros = "0.24"
 syn = { version = "1.0", features = ["full", "extra-traits", "parsing", "printing"]}
-
-[features]
-# Force static linking of LLVM
-llvm-static = ["c2rust-ast-exporter/llvm-static"]