implement a julia specific debug mode with --debug

base/Base.jl

@@ -121,6 +121,23 @@ function setpropertyonce!(x::Module, f::Symbol, desired, success_order::Symbol=:
     return Core.setglobalonce!(x, f, val, success_order, fail_order)
 end
 
+julia_debug::Bool = true
+
+"""
+    isdebug() -> Bool
+
+Return whether the julia session is running in debug mode.
+In debug mode `@assert`s are enabled and `isdebug()` returns `true`.
+This is a compile time setting so and hence a useful pattern is the following:
+
+```
+@static if isdebug()
+    # code that is only enabled in debug mode
+end
+```
+"""
+isdebug() = julia_debug
+
 
 convert(::Type{Any}, Core.@nospecialize x) = x
 convert(::Type{T}, x::T) where {T} = x
@@ -649,6 +666,7 @@ end
 function __init__()
     # Base library init
     global _atexit_hooks_finished = false
+    init_julia_debug()
     Filesystem.__postinit__()
     reinit_stdio()
     Multimedia.reinit_displays() # since Multimedia.displays uses stdout as fallback

base/error.jl

@@ -203,12 +203,13 @@ might decide to check anyways, as an aid to debugging if they fail.
 The optional message `text` is displayed upon assertion failure.
 
 !!! warning
-    An assert might be disabled at some optimization levels.
+    Assertions can be enabled/disabled depending on the `--debug` flag passed to Julia.
     Assert should therefore only be used as a debugging tool
     and not used for authentication verification (e.g., verifying passwords or checking array bounds).
     The code must not rely on the side effects of running `cond` for the correct behavior
     of a function.
 
+
 # Examples
 ```jldoctest
 julia> @assert iseven(3) "3 is an odd number!"
@@ -218,6 +219,9 @@ julia> @assert isodd(3) "What even are numbers?"
 ```
 """
 macro assert(ex, msgs...)
+    enable_asserts = !isdefined(Main, :Base) || Main.Base.julia_debug
+    enable_asserts || return nothing
+
     msg = isempty(msgs) ? ex : msgs[1]
     if isa(msg, AbstractString)
         msg = msg # pass-through

base/exports.jl

@@ -1177,4 +1177,5 @@ public
 # misc
     notnothing,
     runtests,
-    text_colors
+    text_colors,
+    isdebug

base/initdefs.jl

@@ -504,3 +504,11 @@ function disable_library_threading()
     end
     return
 end
+
+function init_julia_debug()
+    opt_julia_debug = Base.JLOptions().julia_debug
+    # `julia_debug` is disabled everywhere or we are in a package and `--debug="script"` is used (default)
+    if opt_julia_debug == 0 || (Base.generating_output() && opt_julia_debug == 1)
+        global julia_debug = false
+    end
+end

base/loading.jl

@@ -1497,31 +1497,36 @@ end
 
 
 struct CacheFlags
-    # OOICCDDP - see jl_cache_flags
+    # OOJICCDDP - see jl_cache_flags
     use_pkgimages::Bool
     debug_level::Int
     check_bounds::Int
     inline::Bool
+    julia_debug::Bool
     opt_level::Int
 end
-function CacheFlags(f::UInt8)
+
+function CacheFlags(f::UInt16)
     use_pkgimages = Bool(f & 1)
     debug_level = Int((f >> 1) & 3)
     check_bounds = Int((f >> 3) & 3)
     inline = Bool((f >> 5) & 1)
-    opt_level = Int((f >> 6) & 3) # define OPT_LEVEL in statiddata_utils
-    CacheFlags(use_pkgimages, debug_level, check_bounds, inline, opt_level)
-end
-CacheFlags(f::Int) = CacheFlags(UInt8(f))
-CacheFlags() = CacheFlags(ccall(:jl_cache_flags, UInt8, ()))
-
-function _cacheflag_to_uint8(cf::CacheFlags)::UInt8
-    f = UInt8(0)
-    f |= cf.use_pkgimages << 0
-    f |= cf.debug_level << 1
-    f |= cf.check_bounds << 3
-    f |= cf.inline << 5
-    f |= cf.opt_level << 6
+    julia_debug = Bool((f >> 6) & 1)
+    opt_level = Int((f >> 7) & 3)
+    CacheFlags(use_pkgimages, debug_level, check_bounds, inline, julia_debug, opt_level)
+end
+
+CacheFlags(f::Int) = CacheFlags(UInt16(f))
+CacheFlags() = CacheFlags(ccall(:jl_cache_flags, UInt16, ()))
+
+function _cacheflag_to_uint16(cf::CacheFlags)::UInt16
+    f = UInt16(0)
+    f |= UInt16(cf.use_pkgimages) << 0
+    f |= UInt16(cf.debug_level) << 1
+    f |= UInt16(cf.check_bounds) << 3
+    f |= UInt16(cf.inline) << 5
+    f |= UInt16(cf.julia_debug) << 6
+    f |= UInt16(cf.opt_level) << 7
     return f
 end
 
@@ -1530,6 +1535,7 @@ function show(io::IO, cf::CacheFlags)
     print(io, ", debug_level = ", cf.debug_level)
     print(io, ", check_bounds = ", cf.check_bounds)
     print(io, ", inline = ", cf.inline)
+    print(io, ", julia_debug = ", cf.julia_debug)
     print(io, ", opt_level = ", cf.opt_level)
 end
 
@@ -2948,7 +2954,7 @@ end
 
 
 function parse_cache_header(f::IO, cachefile::AbstractString)
-    flags = read(f, UInt8)
+    flags = read(f, UInt16)
     modules = Vector{Pair{PkgId, UInt64}}()
     while true
         n = read(f, Int32)
@@ -3404,10 +3410,10 @@ end
         if isempty(modules)
             return true # ignore empty file
         end
-        if @ccall(jl_match_cache_flags(_cacheflag_to_uint8(requested_flags)::UInt8, actual_flags::UInt8)::UInt8) == 0
+        if @ccall(jl_match_cache_flags(_cacheflag_to_uint16(requested_flags)::UInt16, actual_flags::UInt16)::UInt16) == 0
             @debug """
             Rejecting cache file $cachefile for $modkey since the flags are mismatched
-              requested flags: $(requested_flags) [$(_cacheflag_to_uint8(requested_flags))]
+              requested flags: $(requested_flags) [$(_cacheflag_to_uint16(requested_flags))]
               cache file:      $(CacheFlags(actual_flags)) [$actual_flags]
             """
             record_reason(reasons, "mismatched flags")

base/options.jl

@@ -27,6 +27,7 @@ struct JLOptions
     tracked_path::Ptr{UInt8}
     opt_level::Int8
     opt_level_min::Int8
+    julia_debug::Int8
     debug_level::Int8
     check_bounds::Int8
     depwarn::Int8

base/util.jl

@@ -148,8 +148,8 @@ See also [`print`](@ref), [`println`](@ref), [`show`](@ref).
 
 Return a julia command similar to the one of the running process.
 Propagates any of the `--cpu-target`, `--sysimage`, `--compile`, `--sysimage-native-code`,
-`--compiled-modules`, `--pkgimages`, `--inline`, `--check-bounds`, `--optimize`, `--min-optlevel`, `-g`,
-`--code-coverage`, `--track-allocation`, `--color`, `--startup-file`, and `--depwarn`
+`--compiled-modules`, `--pkgimages`, `--inline`, `--check-bounds`, `--optimize`, `--min-optlevel`, `--debug`,
+`-g`, `--code-coverage`, `--track-allocation`, `--color`, `--startup-file`, and `--depwarn`
 command line arguments that are not at their default values.
 
 Among others, `--math-mode`, `--warn-overwrite`, and `--trace-compile` are notably not propagated currently.
@@ -212,6 +212,8 @@ function julia_cmd(julia=joinpath(Sys.BINDIR, julia_exename()); cpu_target::Unio
     opts.use_pkgimages == 2 && push!(addflags, "--pkgimages=existing")
     opts.opt_level == 2 || push!(addflags, "-O$(opts.opt_level)")
     opts.opt_level_min == 0 || push!(addflags, "--min-optlevel=$(opts.opt_level_min)")
+    opts.julia_debug == 0 && push!(addflags, "--debug=no")
+    opts.julia_debug == 2 && push!(addflags, "--debug=yes")
     push!(addflags, "-g$(opts.debug_level)")
     if opts.code_coverage != 0
         # Forward the code-coverage flag only if applicable (if the filename is pid-dependent)

doc/man/julia.1

@@ -182,6 +182,12 @@ Set the optimization level (level 3 if `-O` is used without a level)
 --min-optlevel={0*,1,2,3}
 Set a lower bound on the optimization level
 
+.TP
+--debug={no|script*|yes}
+Control if the `@assert` macro and `isdebug` is `true` nowhere, only in scripts (not packages)\n
+or everywhere, respectively
+
+
 .TP
 -g {0,1*,2}
 Set the level of debug info generation (level 2 if `-g` is used without a level)

pkgimage.mk

@@ -34,11 +34,11 @@ $$(BUILDDIR)/stdlib/$1.release.image: export JULIA_CPU_TARGET=$(JULIA_CPU_TARGET
 $$(BUILDDIR)/stdlib/$1.debug.image: export JULIA_CPU_TARGET=$(JULIA_CPU_TARGET)
 ifneq ($(filter $(1),$(INDEPENDENT_STDLIBS)),)
 $$(BUILDDIR)/stdlib/$1.release.image: $$($1_SRCS) $$(addsuffix .release.image,$$(addprefix $$(BUILDDIR)/stdlib/,$2)) $(build_private_libdir)/sys.$(SHLIB_EXT)
-	@$$(call PRINT_JULIA, $$(call spawn,$$(JULIA_EXECUTABLE)) --startup-file=no --check-bounds=yes -e 'Base.compilecache(Base.identify_package("$1"))')
+	@$$(call PRINT_JULIA, $$(call spawn,$$(JULIA_EXECUTABLE)) --startup-file=no --check-bounds=yes --debug=yes -e 'Base.compilecache(Base.identify_package("$1"))')
 	@$$(call PRINT_JULIA, $$(call spawn,$$(JULIA_EXECUTABLE)) --startup-file=no -e 'Base.compilecache(Base.identify_package("$1"))')
 	touch $$@
 $$(BUILDDIR)/stdlib/$1.debug.image: $$($1_SRCS) $$(addsuffix .debug.image,$$(addprefix $$(BUILDDIR)/stdlib/,$2)) $(build_private_libdir)/sys-debug.$(SHLIB_EXT)
-	@$$(call PRINT_JULIA, $$(call spawn,$$(JULIA_EXECUTABLE)) --startup-file=no --check-bounds=yes -e 'Base.compilecache(Base.identify_package("$1"))')
+	@$$(call PRINT_JULIA, $$(call spawn,$$(JULIA_EXECUTABLE)) --startup-file=no --check-bounds=yes --debug=yes -e 'Base.compilecache(Base.identify_package("$1"))')
 	@$$(call PRINT_JULIA, $$(call spawn,$$(JULIA_EXECUTABLE)) --startup-file=no -e 'Base.compilecache(Base.identify_package("$1"))')
 	touch $$@
 endif

src/jloptions.c

@@ -56,6 +56,7 @@ JL_DLLEXPORT void jl_init_options(void)
                         NULL, // tracked_path
                         2,    // opt_level
                         0,    // opt_level_min
+                        JL_OPTIONS_JULIA_DEBUG_SCRIPT, // julia_debug
 #ifdef JL_DEBUG_BUILD
                         2,    // debug_level [debug build]
 #else
@@ -113,12 +114,14 @@ static const char opts[]  =
     " --compiled-modules={yes*|no|existing|strict}\n"
     "                            Enable or disable incremental precompilation of modules\n"
     " --pkgimages={yes*|no|existing}\n"
-    "                            Enable or disable usage of native code caching in the form of pkgimages ($)\n\n"
+    "                            Enable or disable usage of native code caching in the form of pkgimages ($)\n"
+    "\n"
 
     // actions
     " -e, --eval <expr>          Evaluate <expr>\n"
     " -E, --print <expr>         Evaluate <expr> and display the result\n"
-    " -L, --load <file>          Load <file> immediately on all processors\n\n"
+    " -L, --load <file>          Load <file> immediately on all processors\n"
+    "\n"
 
     // parallel options
     " -t, --threads {auto|N[,auto|M]}\n"
@@ -135,25 +138,30 @@ static const char opts[]  =
     "                           N is set to half of the number of compute threads and M is set to 0 if unspecified.\n"
     " -p, --procs {N|auto}      Integer value N launches N additional local worker processes\n"
     "                           \"auto\" launches as many workers as the number of local CPU threads (logical cores)\n"
-    " --machine-file <file>     Run processes on hosts listed in <file>\n\n"
+    " --machine-file <file>     Run processes on hosts listed in <file>\n"
+    "\n"
 
     // interactive options
     " -i, --interactive          Interactive mode; REPL runs and `isinteractive()` is true\n"
     " -q, --quiet                Quiet startup: no banner, suppress REPL warnings\n"
     " --banner={yes|no|short|auto*}\n"
     "                            Enable or disable startup banner\n"
     " --color={yes|no|auto*}     Enable or disable color text\n"
-    " --history-file={yes*|no}   Load or save history\n\n"
+    " --history-file={yes*|no}   Load or save history\n"
+    "\n"
 
     // error and warning options
     " --depwarn={yes|no*|error}  Enable or disable syntax and method deprecation warnings (`error` turns warnings into errors)\n"
     " --warn-overwrite={yes|no*} Enable or disable method overwrite warnings\n"
-    " --warn-scope={yes*|no}     Enable or disable warning for ambiguous top-level scope\n\n"
+    " --warn-scope={yes*|no}     Enable or disable warning for ambiguous top-level scope\n"
+    "\n"
 
     // code generation options
     " -C, --cpu-target <target>  Limit usage of CPU features up to <target>; set to `help` to see the available options\n"
     " -O, --optimize={0,1,2*,3}  Set the optimization level (level 3 if `-O` is used without a level) ($)\n"
     " --min-optlevel={0*,1,2,3}  Set a lower bound on the optimization level\n"
+    " --debug={no|script*|yes}   Control if the `@assert` macro and `isdebug` is `true` nowhere, only in scripts (not packages)\n"
+    "                            or everywhere, respectively\n"
 #ifdef JL_DEBUG_BUILD
         " -g, --debug-info=[{0,1,2*}] Set the level of debug info generation in the julia-debug build ($)\n"
 #else
@@ -165,6 +173,7 @@ static const char opts[]  =
 #ifdef USE_POLLY
     " --polly={yes*|no}          Enable or disable the polyhedral optimizer Polly (overrides @polly declaration)\n"
 #endif
+    "\n"
 
     // instrumentation options
     " --code-coverage[={none*|user|all}]\n"
@@ -183,6 +192,8 @@ static const char opts[]  =
     "                            Count bytes but only in files that fall under the given file path/directory.\n"
     "                            The `@` prefix is required to select this option. A `@` with no path will track the\n"
     "                            current directory.\n"
+    "\n"
+
     " --bug-report=KIND          Launch a bug report session. It can be used to start a REPL, run a script, or evaluate\n"
     "                            expressions. It first tries to use BugReporting.jl installed in current environment and\n"
     "                            fallbacks to the latest compatible BugReporting.jl if not. For more information, see\n"
@@ -259,9 +270,9 @@ JL_DLLEXPORT void jl_parse_opts(int *argcp, char ***argvp)
            opt_strip_ir,
            opt_heap_size_hint,
            opt_gc_threads,
-           opt_permalloc_pkgimg
+           opt_permalloc_pkgimg,
     };
-    static const char* const shortopts = "+vhqH:e:E:L:J:C:it:p:O:g:";
+    static const char* const shortopts = "+vhqHd:e:E:L:J:C:it:p:O:g:";
     static const struct option longopts[] = {
         // exposed command line options
         // NOTE: This set of required arguments need to be kept in sync
@@ -295,6 +306,7 @@ JL_DLLEXPORT void jl_parse_opts(int *argcp, char ***argvp)
         { "track-allocation",optional_argument, 0, opt_track_allocation },
         { "optimize",        optional_argument, 0, 'O' },
         { "min-optlevel",    optional_argument, 0, opt_optlevel_min },
+        { "debug",           required_argument, 0, 'd' },
         { "debug-info",      optional_argument, 0, 'g' },
         { "check-bounds",    required_argument, 0, opt_check_bounds },
         { "output-bc",       required_argument, 0, opt_output_bc },
@@ -469,6 +481,18 @@ JL_DLLEXPORT void jl_parse_opts(int *argcp, char ***argvp)
             else
                 jl_errorf("julia: invalid argument to --compiled-modules={yes|no|existing|strict} (%s)", optarg);
             break;
+        case 'd':
+            if (!strcmp(optarg,"yes"))
+                jl_options.julia_debug = JL_OPTIONS_JULIA_DEBUG_YES;
+            else if (!strcmp(optarg,"no"))
+                jl_options.julia_debug = JL_OPTIONS_JULIA_DEBUG_NO;
+            else if (!strcmp(optarg,"script")) {
+                jl_options.julia_debug = JL_OPTIONS_JULIA_DEBUG_SCRIPT;
+                printf("opt: %d", jl_options.julia_debug);
+            }
+            else
+                jl_errorf("julia: invalid argument to --debug={yes|script|no} (%s)", optarg);
+            break;
         case opt_pkgimages:
             if (!strcmp(optarg,"yes"))
                 jl_options.use_pkgimages = JL_OPTIONS_USE_PKGIMAGES_YES;

src/jloptions.h

@@ -31,6 +31,7 @@ typedef struct {
     const char *tracked_path;
     int8_t opt_level;
     int8_t opt_level_min;
+    int8_t julia_debug;
     int8_t debug_level;
     int8_t check_bounds;
     int8_t depwarn;

src/julia.h

@@ -2505,6 +2505,10 @@ JL_DLLEXPORT int jl_generating_output(void) JL_NOTSAFEPOINT;
 #define JL_OPTIONS_USE_PKGIMAGES_YES 1
 #define JL_OPTIONS_USE_PKGIMAGES_NO 0
 
+#define JL_OPTIONS_JULIA_DEBUG_YES 2
+#define JL_OPTIONS_JULIA_DEBUG_SCRIPT 1
+#define JL_OPTIONS_JULIA_DEBUG_NO 0
+
 // Version information
 #include <julia_version.h> // Generated file
 

src/staticdata.c

@@ -2898,7 +2898,7 @@ static void jl_write_header_for_incremental(ios_t *f, jl_array_t *worklist, jl_a
     jl_precompile_toplevel_module = (jl_module_t*)jl_array_ptr_ref(worklist, jl_array_len(worklist)-1);
 
     *checksumpos = write_header(f, 0);
-    write_uint8(f, jl_cache_flags());
+    write_uint16(f, jl_cache_flags());
     // write description of contents (name, uuid, buildid)
     write_worklist_for_header(f, worklist);
     // Determine unique (module, abspath, fsize, hash, mtime) dependencies for the files defining modules in the worklist
@@ -2957,7 +2957,7 @@ JL_DLLEXPORT void jl_create_system_image(void **_native_data, jl_array_t *workli
         jl_write_header_for_incremental(f, worklist, mod_array, udeps, srctextpos, &checksumpos);
         if (emit_split) {
             checksumpos_ff = write_header(ff, 1);
-            write_uint8(ff, jl_cache_flags());
+            write_uint16(ff, jl_cache_flags());
             write_mod_list(ff, mod_array);
         }
         else {
@@ -3569,9 +3569,9 @@ static jl_value_t *jl_validate_cache_file(ios_t *f, jl_array_t *depmods, uint64_
         return jl_get_exceptionf(jl_errorexception_type,
                 "Precompile file header verification checks failed.");
     }
-    uint8_t flags = read_uint8(f);
+    uint16_t flags = read_uint16(f);
     if (pkgimage && !jl_match_cache_flags_current(flags)) {
-        return jl_get_exceptionf(jl_errorexception_type, "Pkgimage flags mismatch");
+        return jl_get_exceptionf(jl_errorexception_type, "Pkgimage flags mismatch, current:%d, got:%d", jl_cache_flags(), flags);
     }
     if (!pkgimage) {
         // skip past the worklist