add precompile statements for functions called from main in apps (#649)

remove dependency on at-eval in main

Author: JeffBezanson

src/PackageCompiler.jl

@@ -249,7 +249,8 @@ function create_sysimg_object_file(object_file::String,
                             precompile_statements_file::Vector{String},
                             cpu_target::String,
                             script::Union{Nothing, String},
-                            sysimage_build_args::Cmd)
+                            sysimage_build_args::Cmd,
+                            extra_precompiles::String)
     # Handle precompilation
     precompile_files = String[]
     @debug "running precompilation execution script..."
@@ -301,6 +302,9 @@ function create_sysimg_object_file(object_file::String,
                     @debug "failed to execute \$statement"
                 end
             end
+            @eval PrecompileStagingArea begin
+                $extra_precompiles
+            end
         end # module
         """
 
@@ -418,6 +422,7 @@ function create_sysimage(packages::Union{Nothing, Symbol, Vector{String}, Vector
                          version=nothing,
                          soname=nothing,
                          compat_level::String="major",
+                         extra_precompiles::String = "",
                          )
 
     if filter_stdlibs && incremental
@@ -506,7 +511,8 @@ function create_sysimage(packages::Union{Nothing, Symbol, Vector{String}, Vector
                             precompile_statements_file,
                             cpu_target,
                             script,
-                            sysimage_build_args)
+                            sysimage_build_args,
+                            extra_precompiles)
     object_files = [object_file]
     if julia_init_c_file !== nothing
         push!(object_files, compile_c_init_julia(julia_init_c_file, basename(sysimage_path)))
@@ -700,14 +706,24 @@ function create_app(package_dir::String,
     package_name = ctx.env.pkg.name
     project = dirname(ctx.env.project_file)
 
+    # add precompile statements for functions that will be called from the C main() wrapper
+    precompiles = String[]
+    for (_, julia_main) in executables
+        push!(precompiles, "isdefined($package_name, :$julia_main) && precompile(Tuple{typeof($package_name.$julia_main)})")
+    end
+    push!(precompiles, "precompile(Tuple{typeof(append!), Vector{String}, Vector{Any}})")
+    push!(precompiles, "precompile(Tuple{typeof(empty!), Vector{String}})")
+    push!(precompiles, "precompile(Tuple{typeof(popfirst!), Vector{String}})")
+
     create_sysimage([package_name]; sysimage_path, project,
                     incremental,
                     filter_stdlibs,
                     precompile_execution_file,
                     precompile_statements_file,
                     cpu_target,
                     sysimage_build_args,
-                    include_transitive_dependencies)
+                    include_transitive_dependencies,
+                    extra_precompiles = join(precompiles, "\n"))
 
     for (app_name, julia_main) in executables
         create_executable_from_sysimg(joinpath(app_dir, "bin", app_name), c_driver_program, string(package_name, ".", julia_main))
@@ -717,7 +733,7 @@ end
 
 function create_executable_from_sysimg(exe_path::String,
                                        c_driver_program::String,
-                                       julia_main::String)      
+                                       julia_main::String)
     c_driver_program = abspath(c_driver_program)
     mkpath(dirname(exe_path))
     flags = Base.shell_split(join((cflags(), ldflags(), ldlibs()), " "))

src/embedding_wrapper.c

@@ -102,7 +102,10 @@ int main(int argc, char *argv[]) {
 
     // Update ARGS and PROGRAM_FILE
     checked_eval_string("append!(empty!(Base.ARGS), Core.ARGS)");
-    checked_eval_string("@eval Base PROGRAM_FILE = popfirst!(ARGS)");
+    jl_value_t *firstarg = checked_eval_string("popfirst!(ARGS)");
+    JL_GC_PUSH1(&firstarg);
+    jl_set_global(jl_base_module, jl_symbol("PROGRAM_FILE"), firstarg);
+    JL_GC_POP();
 
     // call the work function, and get back a value
     jl_value_t *jl_retcode = checked_eval_string(JULIA_MAIN "()");