disable assert macro unless running in debug mode

Author: KristofferC

base/Base.jl

@@ -66,6 +66,9 @@ time_ns() = ccall(:jl_hrtime, UInt64, ())
 
 start_base_include = time_ns()
 
+julia_debug = true
+isdebug() = julia_debug::Bool
+
 ## Load essential files and libraries
 include("essentials.jl")
 include("ctypes.jl")
@@ -396,6 +399,7 @@ in_sysimage(pkgid::PkgId) = pkgid in _sysimage_modules
 
 if is_primary_base_module
 function __init__()
+    global julia_debug = Base.JLOptions().debug_level >= 2
     # try to ensuremake sure OpenBLAS does not set CPU affinity (#1070, #9639)
     if !haskey(ENV, "OPENBLAS_MAIN_FREE") && !haskey(ENV, "GOTOBLAS_MAIN_FREE")
         ENV["OPENBLAS_MAIN_FREE"] = "1"

base/error.jl

@@ -190,14 +190,8 @@ windowserror(p, code::UInt32=Libc.GetLastError(); extrainfo=nothing) = throw(Mai
     @assert cond [text]
 
 Throw an [`AssertionError`](@ref) if `cond` is `false`. Preferred syntax for writing assertions.
-Message `text` is optionally displayed upon assertion failure.
-
-!!! warning
-    An assert might be disabled at various optimization levels.
-    Assert should therefore only be used as a debugging tool
-    and not used for authentication verification (e.g., verifying passwords),
-    nor should side effects needed for the function to work correctly
-    be used inside of asserts.
+Message `text` is optionally displayed upon assertion failure. Only active when julia is started
+in debug mode (`julia -g`).
 
 # Examples
 ```jldoctest
@@ -208,6 +202,7 @@ julia> @assert isodd(3) "What even are numbers?"
 ```
 """
 macro assert(ex, msgs...)
+    @isdefined(isdebug) && !(isdebug()) && return nothing
     msg = isempty(msgs) ? ex : msgs[1]
     if isa(msg, AbstractString)
         msg = msg # pass-through

base/loading.jl

@@ -1481,9 +1481,9 @@ function get_preferences(uuid::UUID, cache::TOMLCache = TOMLCache();
     # Fall back to default value of "no preferences".
     return Dict{String,Any}()
 end
-get_preferences_hash(uuid::UUID, cache::TOMLCache = TOMLCache()) = UInt64(hash(get_preferences(uuid, cache)))
+get_preferences_hash(uuid::UUID, cache::TOMLCache = TOMLCache()) = UInt64(hash(julia_debug, hash(get_preferences(uuid, cache))))
 get_preferences_hash(m::Module, cache::TOMLCache = TOMLCache()) = get_preferences_hash(PkgId(m).uuid, cache)
-get_preferences_hash(::Nothing, cache::TOMLCache = TOMLCache()) = UInt64(hash(Dict{String,Any}()))
+get_preferences_hash(::Nothing, cache::TOMLCache = TOMLCache()) = UInt64(hash(julia_debug, hash(Dict{String,Any}())))
 
 
 # returns true if it "cachefile.ji" is stale relative to "modpath.jl"

doc/Makefile

@@ -7,7 +7,7 @@ SRCDIR           := $(abspath $(dir $(lastword $(MAKEFILE_LIST))))
 JULIAHOME        := $(abspath $(SRCDIR)/..)
 SRCCACHE         := $(abspath $(JULIAHOME)/deps/srccache)
 include $(JULIAHOME)/Make.inc
-JULIA_EXECUTABLE := $(call spawn,$(build_bindir)/julia) --startup-file=no
+JULIA_EXECUTABLE := $(call spawn,$(build_bindir)/julia) --startup-file=no -g2
 
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