Make trimmed binaries initialize on first call (#58141)

Author: gbaraldi

contrib/juliac.jl

@@ -88,8 +88,6 @@ allflags = Base.shell_split(allflags)
 rpath = get_rpath(; relative = relative_rpath)
 rpath = Base.shell_split(rpath)
 tmpdir = mktempdir(cleanup=false)
-initsrc_path = joinpath(tmpdir, "init.c")
-init_path = joinpath(tmpdir, "init.a")
 img_path = joinpath(tmpdir, "img.a")
 bc_path = joinpath(tmpdir, "img-bc.a")
 
@@ -122,19 +120,6 @@ function compile_products(enable_trim::Bool)
         exit(1)
     end
 
-    # Compile the initialization code
-    open(initsrc_path, "w") do io
-        print(io, """
-                  #include <julia.h>
-                  __attribute__((constructor)) void static_init(void) {
-                      if (jl_is_initialized())
-                          return;
-                      julia_init(JL_IMAGE_IN_MEMORY);
-                      jl_exception_clear();
-                  }
-                  """)
-    end
-    run(`cc $(cflags) -g -c -o $init_path $initsrc_path`)
 end
 
 function link_products()
@@ -150,11 +135,11 @@ function link_products()
     julia_libs = Base.shell_split(Base.isdebugbuild() ? "-ljulia-debug -ljulia-internal-debug" : "-ljulia -ljulia-internal")
     try
         if output_type == "--output-lib"
-            cmd2 = `cc $(allflags) $(rpath) -o $outname -shared -Wl,$(Base.Linking.WHOLE_ARCHIVE) $img_path  -Wl,$(Base.Linking.NO_WHOLE_ARCHIVE) $init_path  $(julia_libs)`
+            cmd2 = `cc $(allflags) $(rpath) -o $outname -shared -Wl,$(Base.Linking.WHOLE_ARCHIVE) $img_path  -Wl,$(Base.Linking.NO_WHOLE_ARCHIVE)  $(julia_libs)`
         elseif output_type == "--output-sysimage"
             cmd2 = `cc $(allflags) $(rpath) -o $outname -shared -Wl,$(Base.Linking.WHOLE_ARCHIVE) $img_path  -Wl,$(Base.Linking.NO_WHOLE_ARCHIVE)             $(julia_libs)`
         else
-            cmd2 = `cc $(allflags) $(rpath) -o $outname -Wl,$(Base.Linking.WHOLE_ARCHIVE) $img_path -Wl,$(Base.Linking.NO_WHOLE_ARCHIVE) $init_path $(julia_libs)`
+            cmd2 = `cc $(allflags) $(rpath) -o $outname -Wl,$(Base.Linking.WHOLE_ARCHIVE) $img_path -Wl,$(Base.Linking.NO_WHOLE_ARCHIVE)  $(julia_libs)`
         end
         verbose && println("Running: $cmd2")
         run(cmd2)

src/jlapi.c

@@ -88,7 +88,17 @@ JL_DLLEXPORT void jl_init_with_image(const char *julia_bindir,
     if (jl_is_initialized())
         return;
     libsupport_init();
-    jl_options.julia_bindir = julia_bindir;
+    if (julia_bindir) {
+        jl_options.julia_bindir = julia_bindir;
+    } else {
+#ifdef _OS_WINDOWS_
+        jl_options.julia_bindir = strdup(jl_get_libdir());
+#else
+        int written = asprintf((char**)&jl_options.julia_bindir, "%s" PATHSEPSTRING ".." PATHSEPSTRING "%s", jl_get_libdir(), "bin");
+        if (written < 0)
+            abort(); // unexpected: memory allocation failed
+#endif
+    }
     if (image_path != NULL)
         jl_options.image_file = image_path;
     else
@@ -105,18 +115,7 @@ JL_DLLEXPORT void jl_init_with_image(const char *julia_bindir,
  */
 JL_DLLEXPORT void jl_init(void)
 {
-    char *libbindir = NULL;
-#ifdef _OS_WINDOWS_
-    libbindir = strdup(jl_get_libdir());
-#else
-    (void)asprintf(&libbindir, "%s" PATHSEPSTRING ".." PATHSEPSTRING "%s", jl_get_libdir(), "bin");
-#endif
-    if (!libbindir) {
-        printf("jl_init unable to find libjulia!\n");
-        abort();
-    }
-    jl_init_with_image(libbindir, jl_get_default_sysimg_path());
-    free(libbindir);
+    jl_init_with_image(NULL, jl_get_default_sysimg_path());
 }
 
 static void _jl_exception_clear(jl_task_t *ct) JL_NOTSAFEPOINT

src/julia_internal.h

@@ -3,6 +3,7 @@
 #ifndef JL_INTERNAL_H
 #define JL_INTERNAL_H
 
+#include "dtypes.h"
 #include "options.h"
 #include "julia_assert.h"
 #include "julia_locks.h"
@@ -192,6 +193,8 @@ void JL_UV_LOCK(void);
 extern _Atomic(unsigned) _threadedregion;
 extern _Atomic(uint16_t) io_loop_tid;
 
+JL_DLLEXPORT void jl_enter_threaded_region(void);
+JL_DLLEXPORT void jl_exit_threaded_region(void);
 int jl_running_under_rr(int recheck) JL_NOTSAFEPOINT;
 
 //--------------------------------------------------

src/threading.c

@@ -1,11 +1,9 @@
 // This file is a part of Julia. License is MIT: https://julialang.org/license
-
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <inttypes.h>
-
 #include "julia.h"
 #include "julia_internal.h"
 #include "julia_assert.h"
@@ -457,15 +455,16 @@ JL_DLLEXPORT jl_gcframe_t **jl_autoinit_and_adopt_thread(void)
 {
     if (!jl_is_initialized()) {
         void *retaddr = __builtin_extract_return_addr(__builtin_return_address(0));
-        void *sysimg_handle = jl_find_dynamic_library_by_addr(retaddr, /* throw_err */ 0);
-
-        if (sysimg_handle == NULL) {
+        void *handle = jl_find_dynamic_library_by_addr(retaddr, 0);
+        if (handle == NULL) {
             fprintf(stderr, "error: runtime auto-initialization failed due to bad sysimage lookup\n"
                             "       (this should not happen, please file a bug report)\n");
-            abort();
+            exit(1);
         }
-
-        assert(0 && "TODO: implement auto-init");
+        const char *image_path = jl_pathname_for_handle(handle);
+        jl_enter_threaded_region(); // This should maybe be behind a lock, but it's harmless if done twice
+        jl_init_with_image(NULL, image_path);
+        return &jl_get_current_task()->gcstack;
     }
 
     return jl_adopt_thread();