Build partition_alloc

base/BUILD.gn

@@ -1087,6 +1087,25 @@ component("base") {
     "//third_party/abseil-cpp:absl",
   ]
 
+  if (is_cobalt && is_starboard && current_toolchain == cobalt_toolchain) {
+    import("//cobalt/build/configs/modular_variables.gni")
+    if (use_custom_libc) {
+      if (is_starboard && current_toolchain == cobalt_toolchain) {
+        deps -= [ "//base/allocator/partition_allocator:raw_ptr" ]
+
+        # TODO: b/330221826 Change to |public_configs| with matching dependencies.
+        # all_dependent_configs += [ ":starboard_config" ]
+      }
+    }
+  }
+
+  if (is_cobalt && is_starboard && current_toolchain == cobalt_toolchain) {
+    import("//cobalt/build/configs/modular_variables.gni")
+    if (use_custom_libc) {
+      deps += [ "//starboard:starboard_group" ]
+    }
+  }
+
   if (build_rust_base_conversions) {
     # Base provides conversions between CXX types and base types (e.g.
     # StringPiece).
@@ -1627,7 +1646,7 @@ component("base") {
       ]
     }
 
-    if (is_posix) {
+    if (is_posix && !is_cobalt) {
       sources += [
         "base_paths_posix.h",
         "memory/madv_free_discardable_memory_allocator_posix.cc",

base/allocator/partition_allocator/BUILD.gn

@@ -214,15 +214,15 @@ component("partition_alloc") {
       "partition_alloc_base/time/time_win.cc",
       "partition_tls_win.cc",
     ]
-  } else if (is_posix) {
+  } else if (is_posix && !is_cobalt) {
     sources += [
       "page_allocator_internals_posix.cc",
       "page_allocator_internals_posix.h",
       "partition_alloc_base/files/file_util.h",
       "partition_alloc_base/files/file_util_posix.cc",
       "partition_alloc_base/posix/safe_strerror.cc",
       "partition_alloc_base/posix/safe_strerror.h",
-      "partition_alloc_base/rand_util_posix.cc",
+      # "partition_alloc_base/rand_util_posix.cc",
       "partition_alloc_base/threading/platform_thread_internal_posix.h",
       "partition_alloc_base/threading/platform_thread_posix.cc",
       "partition_alloc_base/time/time_conversion_posix.cc",
@@ -320,6 +320,13 @@ component("partition_alloc") {
     # tagging.cc requires __arm_mte_set_* functions.
     deps += [ "//third_party/android_ndk:cpu_features" ]
   }
+
+  if (is_cobalt && is_starboard && current_toolchain == cobalt_toolchain) {
+    import("//cobalt/build/configs/modular_variables.gni")
+    if (use_custom_libc) {
+      deps += [ "//starboard:starboard_group" ]
+    }
+  }
   if (is_fuchsia) {
     public_deps += [
       "//third_party/fuchsia-sdk/sdk/pkg/fit",

base/allocator/partition_allocator/partition_alloc_config.h

@@ -65,7 +65,7 @@ static_assert(sizeof(void*) != 8, "");
 #endif
 
 #if BUILDFLAG(HAS_64_BIT_POINTERS) && \
-    (BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_ANDROID))
+    (BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_ANDROID)) && !BUILDFLAG(IS_STARBOARD)
 #include <linux/version.h>
 // TODO(bikineev): Enable for ChromeOS.
 #define PA_CONFIG_STARSCAN_UFFD_WRITE_PROTECTOR_SUPPORTED() \
@@ -104,7 +104,7 @@ static_assert(sizeof(void*) != 8, "");
 // POSIX is not only UNIX, e.g. macOS and other OSes. We do use Linux-specific
 // features such as futex(2).
 #define PA_CONFIG_HAS_LINUX_KERNEL() \
-  (BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS) || BUILDFLAG(IS_ANDROID))
+  (BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS) || BUILDFLAG(IS_ANDROID)) && !BUILDFLAG(IS_STARBOARD)
 
 // On some platforms, we implement locking by spinning in userspace, then going
 // into the kernel only if there is contention. This requires platform support,

build/config/c++/BUILD.gn

@@ -68,6 +68,34 @@ config("runtime_library") {
       "-isystem" + rebase_path("$libcxx_prefix/include", root_build_dir),
       "-isystem" + rebase_path("$libcxxabi_prefix/include", root_build_dir),
     ]
+    if (is_cobalt && is_starboard && current_toolchain == cobalt_toolchain) {
+      import("//cobalt/build/configs/modular_variables.gni")
+      if (use_custom_libc) {
+        # if (is_cobalt) {
+        #   import("//cobalt/build/configs/modular_variables.gni")
+        #   if (is_starboard && current_toolchain == cobalt_toolchain &&
+        #       use_custom_libc) {
+        #     deps = [
+        #       "//third_party/llvm-project/compiler-rt:compiler_rt",
+        #       "//third_party/musl:c",
+        #     ]
+        #     all_dependent_configs = [ "//starboard/build/config/modular/x64" ]
+        #   }
+        # }
+        cflags_cc += [
+          "-isystem" +
+              rebase_path("//third_party/musl/include", root_build_dir),
+          "-isystem" +
+              rebase_path("//third_party/musl/arch/generic", root_build_dir),
+        ]
+        cflags_c = [
+          "-isystem" +
+              rebase_path("//third_party/musl/include", root_build_dir),
+          "-isystem" +
+              rebase_path("//third_party/musl/arch/generic", root_build_dir),
+        ]
+      }
+    }
 
     cflags_objcc = cflags_cc
 
@@ -87,10 +115,11 @@ config("runtime_library") {
       # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83931); -nodefaultlibs
       # removes all of the default libraries, so add back the ones that we need.
       libs += [
-        "c",
+        # "c",
         "gcc_s",
         "m",
-        "rt",
+
+        # "rt",
       ]
     }
   }

buildtools/third_party/libc++/BUILD.gn

@@ -54,6 +54,13 @@ target(_libcxx_target_type, "libc++") {
     "//build/config:common_deps",
     "//third_party/catapult/devil:devil",
   ]
+  if (is_cobalt && is_starboard && current_toolchain == cobalt_toolchain) {
+    import("//cobalt/build/configs/modular_variables.gni")
+    if (use_custom_libc) {
+      visibility += [ "//starboard:starboard_group" ]
+    }
+  }
+
   if (is_linux) {
     # This target packages libc++.so, so must have an explicit dependency on
     # libc++.
@@ -115,6 +122,12 @@ target(_libcxx_target_type, "libc++") {
     "trunk/src/verbose_abort.cpp",
   ]
 
+  if (is_cobalt && is_starboard && current_toolchain == cobalt_toolchain) {
+    import("//cobalt/build/configs/modular_variables.gni")
+    if (use_custom_libc) {
+     sources-= [ "trunk/src/atomic.cpp",]
+    }}
+
   if (enable_iterator_debugging) {
     sources += [
       "trunk/src/debug.cpp",
@@ -210,4 +223,14 @@ target(_libcxx_target_type, "libc++") {
       deps = [ "//buildtools/third_party/libc++abi" ]
     }
   }
+  if (is_cobalt) {
+    import("//cobalt/build/configs/modular_variables.gni")
+    if (is_starboard && current_toolchain == cobalt_toolchain &&
+        use_custom_libc) {
+      deps += [
+        "//third_party/llvm-project/compiler-rt:compiler_rt",
+        "//third_party/musl:c",
+      ]
+    }
+  }
 }

buildtools/third_party/libc++abi/BUILD.gn

@@ -13,6 +13,12 @@ source_set("libc++abi") {
   } else {
     visibility = [ "//buildtools/third_party/libc++" ]
   }
+  if (is_cobalt && is_starboard && current_toolchain == cobalt_toolchain) {
+    import("//cobalt/build/configs/modular_variables.gni")
+    if (use_custom_libc) {
+      visibility += [ "//starboard:starboard_group" ]
+    }
+  }
 
   # Fuchsia builds don't link against any libraries that provide stack
   # unwinding symbols, unlike Linux does with glibc (same applies for Android).
@@ -21,6 +27,14 @@ source_set("libc++abi") {
     deps = [ "//buildtools/third_party/libunwind" ]
   }
 
+  if (is_cobalt) {
+    import("//cobalt/build/configs/modular_variables.gni")
+    if (is_starboard && current_toolchain == cobalt_toolchain &&
+        use_custom_libc) {
+      deps = [ "//third_party/musl:c" ]
+    }
+  }
+
   sources = [
     "trunk/src/abort_message.cpp",
     "trunk/src/cxa_aux_runtime.cpp",

cobalt/build/configs/BUILD.gn

@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import("//cobalt/build/configs/modular_variables.gni")
 import("//starboard/build/buildflags.gni")
 
 config("cobalt_config") {
@@ -21,8 +22,12 @@ config("cobalt_config") {
   ]
   if (current_toolchain == starboard_toolchain) {
     configs += [ "//${starboard_path}/platform_configuration" ]
-  } else if (current_toolchain == cobalt_toolchain) {
-    # TODO(nyardi) : Add modular/cobalt toolchain configs as needed"
+  } else if (current_toolchain == cobalt_toolchain && is_starboard &&
+             use_custom_libc) {
+    configs += [
+      "//starboard/build/config/modular/x64",
+      "//starboard/build/config:starboard",
+    ]
   } else {
     # No configs to add for any other toolchain
   }

cobalt/build/configs/linux-x64x11/args.gn

@@ -15,3 +15,8 @@ media_use_ffmpeg = false
 # Overriding flag from components/nacl/features.gni
 # NACL platform is deprecated in 2022 : https://sites.google.com/a/google.com/sandboxing-mitigations/reviews/nacl
 enable_nacl = false
+
+use_custom_libcxx = true
+
+use_partition_alloc = false
+enable_pkeys = false

starboard/BUILD.gn

@@ -169,7 +169,68 @@ if (!is_cobalt) {
   }
 } else {
   group("starboard_group") {
-    deps = [ "//starboard($starboard_toolchain)" ]
+    deps = []
+    public_deps = [
+      ":starboard_headers_only",
+      "//starboard/client_porting/eztime",
+    ]
+
+    if (sb_is_modular && current_toolchain == cobalt_toolchain) {
+      public_deps += [
+        "//buildtools/third_party/libc++",
+        "//buildtools/third_party/libc++abi",
+        "//third_party/llvm-project/compiler-rt:compiler_rt",
+        "//third_party/musl:c",
+      ]
+
+      if (!sb_is_evergreen) {
+        # For modular builds, we need to wrap any POSIX APIs that may not be ABI
+        # equivalent across the Cobalt toolchain and the platform toolchain. For
+        # non-Evergreen builds, this is done via the below wrapper implementations
+        # of the API functions, which will simply call a renamed version of the
+        # function that will be implemented in the Starboard shared library. The
+        # same behavior is achieved in Evergreen via exported_symbols.cc remapping
+        # the functions to the same renamed version. In both cases, implementation
+        # of these renamed functions will handle translating data types across the
+        # ABI boundary and be compiled into the Starboard shared library in
+        # //starboard/build/config/starboard_target_type.gni.
+        deps += [ "//starboard/shared/modular:cobalt_layer_posix_abi_wrappers" ]
+      }
+
+      if (sb_is_evergreen) {
+        public_deps += [ "//starboard/elf_loader:sabi_string" ]
+      } else {
+        data_deps = [ ":starboard($starboard_toolchain)" ]
+      }
+
+      # TODO: b/295702296 Fix libunwind for modular builds.
+      if (sb_is_evergreen) {
+        public_deps += [ "//third_party/llvm-project/libunwind:unwind" ]
+      }
+    } else {
+      public_deps += [
+        ":starboard($starboard_toolchain)",
+        "//starboard/common",
+      ]
+
+      if (enable_evergreen_code) {
+        if (!sb_is_modular || sb_is_evergreen) {
+          if (sb_is_evergreen_compatible &&
+              current_toolchain == starboard_toolchain) {
+            public_deps += [ "//starboard/crashpad_wrapper" ]
+          } else {
+            public_deps += [ "//starboard/crashpad_wrapper:wrapper_stub" ]
+          }
+        }
+      }
+
+      if (final_executable_type == "shared_library" &&
+          current_toolchain != default_toolchain) {
+        set_defaults("executable") {
+          sources = [ "//starboard/shared/starboard/shared_main_adapter.cc" ]
+        }
+      }
+    }
   }
 }
 

starboard/build/config/modular/BUILD.gn

@@ -18,19 +18,11 @@ config("modular") {
     "-ffunction-sections",
     "-fdata-sections",
     "-nostdlibinc",
-    "-isystem" + rebase_path("//third_party/llvm-project/libcxxabi/include",
-                             root_build_dir),
-    "-isystem" + rebase_path("//third_party/llvm-project/libunwind/include",
-                             root_build_dir),
-    "-isystem" + rebase_path("//third_party/llvm-project/libcxx/include",
-                             root_build_dir),
-    "-isystem" + rebase_path("//third_party/musl/include", root_build_dir),
-    "-isystem" + rebase_path("//third_party/musl/arch/generic", root_build_dir),
   ]
 
   cflags += [ "-fPIC" ]
 
-  cflags_cc = [ "-nostdinc++" ]
+  # cflags_cc = [ "-nostdinc++" ]
 
   defines = [
     # Ensure that the Starboardized __external_threading file is included.

third_party/abseil-cpp/absl/base/internal/direct_mmap.h

@@ -24,8 +24,7 @@
 
 #include <sys/mman.h>
 
-#ifdef __linux__
-
+#if defined(__linux__) && !defined(STARBOARD)
 #include <sys/types.h>
 #ifdef __BIONIC__
 #include <sys/syscall.h>

third_party/llvm-project/compiler-rt/BUILD.gn

@@ -92,5 +92,4 @@ static_library("compiler_rt") {
   }
 
   configs += [ ":compiler_rt_config" ]
-  configs -= [ "//starboard/build/config:default_cpp_standard" ]
 }

third_party/musl/BUILD.gn

@@ -24,7 +24,7 @@ if (target_cpu == "x64") {
 
 config("external_settings") {
   include_dirs = [
-    "musl/include",
+    "include",
     "arch/$musl_arch",
     "arch/generic",
   ]
@@ -518,7 +518,7 @@ static_library("c_internal") {
   }
 
   deps = [
-    "//starboard:starboard_headers_only",
+    "//starboard:starboard_headers_only", 
     "//starboard/client_porting/eztime",
     "//starboard/common:common_headers_only",
   ]