rtld: remove crt{begin,end}.S and define __dso_handle in c++

managarm · Oct 16, 2024 · 536c134 · 536c134
1 parent a3cabed
commit 536c134
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Showing 14 changed files with 5 additions and 310 deletions.
diff --git a/meson.build b/meson.build
@@ -372,17 +372,11 @@ internal_sources = [
 	'options/internal/generic/search.cpp',
 	'options/internal/gcc/stack_protector.cpp',
 	'options/internal/gcc/guard-abi.cpp',
-	'options/internal/gcc/initfini.cpp',
 	'options/internal/gcc-extra/cxxabi.cpp',
 	'options/internal' / host_machine.cpu_family() / 'setjmp.S',
 	'options/internal' / host_machine.cpu_family() / 'fenv.S',
 ]
 
-internal_dso_sources = [
-	'options/internal' / host_machine.cpu_family() / 'mlibc_crtbegin.S',
-	'options/internal' / host_machine.cpu_family() / 'mlibc_crtend.S',
-]
-
 if not no_headers
 	install_headers(
 		'options/internal/include/stdint.h'
@@ -520,7 +514,7 @@ if not headers_only
 		)
 		hide_everything_ld = (meson.current_source_dir()
 				      / 'scripts/hide-everything.ld')
-		libc_shared = shared_library('c', libc_all_sources + internal_dso_sources,
+		libc_shared = shared_library('c', libc_all_sources,
 			cpp_args: [libc_cpp_args],
 			include_directories: libc_include_dirs,
 			dependencies: libc_deps + rtlib_deps,

diff --git a/options/internal/aarch64/mlibc_crtbegin.S b/options/internal/aarch64/mlibc_crtbegin.S
diff --git a/options/internal/aarch64/mlibc_crtend.S b/options/internal/aarch64/mlibc_crtend.S
diff --git a/options/internal/gcc/initfini.cpp b/options/internal/gcc/initfini.cpp
diff --git a/options/internal/m68k/mlibc_crtbegin.S b/options/internal/m68k/mlibc_crtbegin.S
diff --git a/options/internal/m68k/mlibc_crtend.S b/options/internal/m68k/mlibc_crtend.S
diff --git a/options/internal/riscv64/mlibc_crtbegin.S b/options/internal/riscv64/mlibc_crtbegin.S
diff --git a/options/internal/riscv64/mlibc_crtend.S b/options/internal/riscv64/mlibc_crtend.S
diff --git a/options/internal/x86/mlibc_crtbegin.S b/options/internal/x86/mlibc_crtbegin.S
diff --git a/options/internal/x86/mlibc_crtend.S b/options/internal/x86/mlibc_crtend.S
diff --git a/options/internal/x86_64/mlibc_crtbegin.S b/options/internal/x86_64/mlibc_crtbegin.S
diff --git a/options/internal/x86_64/mlibc_crtend.S b/options/internal/x86_64/mlibc_crtend.S
diff --git a/options/lsb/generic/dso_exit.cpp b/options/lsb/generic/dso_exit.cpp
@@ -48,7 +48,9 @@ extern "C" void __cxa_finalize(void *dso) {
 	}
 }
 
-extern "C" void *__dso_handle;
+// This is referenced by the compiler when generating constructors for global
+// C++ objects so that it can call __cxa_finalize with a unique argument.
+extern "C" { [[gnu::visibility("hidden")]] void *__dso_handle; }
 
 [[gnu::destructor]] void __mlibc_do_destructors() {
 	// In normal programs this call to __cxa_finalize is provided by libgcc.

diff --git a/tests/meson.build b/tests/meson.build
@@ -175,11 +175,7 @@ if library_type == 'static'
 	use_pie = false
 	test_c_args += '-no-pie'
 	test_link_args += ['-no-pie', '-static']
-	test_sources += [
-		'../options/internal' / host_machine.cpu_family() / 'mlibc_crtbegin.S',
-		'../options/internal' / host_machine.cpu_family() / 'mlibc_crtend.S',
-		crt,
-	]
+	test_sources += crt
 else
 	libc_dep = declare_dependency(
 		include_directories: libc_include_dirs,