tools+libluna: Make new and delete weak to avoid conflicts with libstdc++

Wasn't causing problems earlier, but when trying to rebuild the toolchain, it failed because of this.

libluna/CMakeLists.txt

@@ -51,6 +51,9 @@ add_library(luna ${SOURCES})
 target_compile_options(luna PRIVATE ${COMMON_FLAGS})
 target_include_directories(luna PUBLIC include/)
 target_include_directories(luna PUBLIC ${LUNA_BASE}/usr/include)
+if(DEFINED LIBC_BOOTSTRAP)
+target_compile_definitions(luna PUBLIC LIBC_BOOTSTRAP)
+endif()
 
 if("${LUNA_ARCH}" MATCHES "x86_64")
 target_compile_options(luna-freestanding PRIVATE -mno-red-zone)

libluna/src/Heap.cpp

@@ -420,35 +420,39 @@ void dump_heap_usage()
     dbgln("-- Heap memory in use: %zu bytes", alloc_used);
 }
 
-// Otherwise, this is defined in libstdc++.
+#if defined(USE_FREESTANDING) || defined(LIBC_BOOTSTRAP)
-#ifdef USE_FREESTANDING
+#define WEAK
-void* operator new(usize size, const std::nothrow_t&) noexcept
+#else
-{
+#define WEAK __attribute__((weak))
-    return malloc_impl(size, false, false).value_or(nullptr);
-}
-
-void* operator new[](usize size, const std::nothrow_t&) noexcept
-{
-    return malloc_impl(size, false, false).value_or(nullptr);
-}
-
-void operator delete(void* p) noexcept
-{
-    free_impl(p);
-}
-
-void operator delete[](void* p) noexcept
-{
-    free_impl(p);
-}
-
-void operator delete(void* p, usize) noexcept
-{
-    free_impl(p);
-}
-
-void operator delete[](void* p, usize) noexcept
-{
-    free_impl(p);
-}
 #endif
+
+// If libstdc++ is linked, it should override these definitions.
+void* WEAK operator new(usize size, const std::nothrow_t&) noexcept
+{
+    return malloc_impl(size, false, false).value_or(nullptr);
+}
+
+void* WEAK operator new[](usize size, const std::nothrow_t&) noexcept
+{
+    return malloc_impl(size, false, false).value_or(nullptr);
+}
+
+void WEAK operator delete(void* p) noexcept
+{
+    free_impl(p);
+}
+
+void WEAK operator delete[](void* p) noexcept
+{
+    free_impl(p);
+}
+
+void WEAK operator delete(void* p, usize) noexcept
+{
+    free_impl(p);
+}
+
+void WEAK operator delete[](void* p, usize) noexcept
+{
+    free_impl(p);
+}

tools/setup-gcc.sh

@@ -64,7 +64,7 @@ make install-gcc
 make install-target-libgcc
 
 mkdir -p $LUNA_BUILD_DIR
-cmake -S $LUNA_ROOT -B $LUNA_BUILD_DIR -G "$LUNA_CMAKE_GENERATOR_NAME"
+cmake -S $LUNA_ROOT -B $LUNA_BUILD_DIR -G "$LUNA_CMAKE_GENERATOR_NAME" -DLIBC_BOOTSTRAP=1
 cmake --build $LUNA_BUILD_DIR --target libc
 
 make all-target-libstdc++-v3 CXXFLAGS_FOR_TARGET="-fno-exceptions" -j$(nproc)