Issue 1:
To reproduce:

Clone the current (804d12ebe3801f7faf8cea234ffe6ec2452443c8) Julia repo.

Build with make

Run ./julia

Type import Pkg and then Pkg.update().

/julia
_
_ _ _(_)_ | Documentation: https://docs.julialang.org
(_) | (_) (_) |
_ _ _| |_ __ _ | Type "?" for help, "]?" for Pkg help.
| | | | | | |/ _` | |
| | |_| | | | (_| | | Version 1.1.0-DEV.unknown (2018-08-31)
_/ |\__'_|_|_|\__'_| | Commit 804d12e (0 days old master)
|__/ |

julia> import Pkg

julia> Pkg.update()
Cloning default registries into /home/openpower.student18/.julia/registries
Cloning registry General from "https://github.com/JuliaRegistries/General.git"

signal (11): Segmentation fault
in expression starting at no file:0
set_ssl_cert_locations at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/LibGit2/src/error.jl:0
initialize at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/LibGit2/src/LibGit2.jl:990
ensure_initialized at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/LibGit2/src/LibGit2.jl:967 [inlined]
Type at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/LibGit2/src/config.jl:50
Type at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/LibGit2/src/config.jl:50 [inlined]
Type at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/LibGit2/src/types.jl:1340 [inlined]
#CredentialPayload#32 at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/LibGit2/src/types.jl:1350 [inlined]
Type at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/LibGit2/src/types.jl:1350 [inlined]
#clone#131 at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/LibGit2/src/LibGit2.jl:559
unknown function (ip: 0x7fff60538347)
jl_fptr_trampoline at /home/openpower.student18/tmp/julia/src/gf.c:1841
jl_apply_generic at /home/openpower.student18/tmp/julia/src/gf.c:2196
jl_apply at /home/openpower.student18/tmp/julia/src/julia.h:1558 [inlined]
jl_invoke at /home/openpower.student18/tmp/julia/src/gf.c:56
#clone at ./none:0 [inlined]
#clone#2 at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/Pkg/src/GitTools.jl:94
jl_fptr_args at /home/openpower.student18/tmp/julia/src/gf.c:1851
jl_fptr_trampoline at /home/openpower.student18/tmp/julia/src/gf.c:1841
jl_apply_generic at /home/openpower.student18/tmp/julia/src/gf.c:2196
jl_apply at /home/openpower.student18/tmp/julia/src/julia.h:1558 [inlined]
jl_invoke at /home/openpower.student18/tmp/julia/src/gf.c:56
#50 at ./none:0
shred! at ./secretbuffer.jl:184
#registries#49 at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/Pkg/src/Types.jl:923
jfptr_#registries#49_9962 at /home/openpower.student18/tmp/julia/usr/lib/julia/sys.so (unknown line)
jl_invoke at /home/openpower.student18/tmp/julia/src/gf.c:42
registries at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/Pkg/src/Types.jl:907 [inlined]
macro expansion at ./logging.jl:307 [inlined]
update_registry at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/Pkg/src/API.jl:96
#up#31 at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/Pkg/src/API.jl:166
unknown function (ip: 0x7fff605319f3)
jl_fptr_trampoline at /home/openpower.student18/tmp/julia/src/gf.c:1841
jl_apply_generic at /home/openpower.student18/tmp/julia/src/gf.c:2196
jl_apply at /home/openpower.student18/tmp/julia/src/julia.h:1558 [inlined]
jl_invoke at /home/openpower.student18/tmp/julia/src/gf.c:56
up at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/Pkg/src/API.jl:158 [inlined]
#up#30 at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/Pkg/src/API.jl:154 [inlined]
up at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/Pkg/src/API.jl:154 [inlined]
#up#27 at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/Pkg/src/API.jl:151 [inlined]
up at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/Pkg/src/API.jl:151
jl_fptr_args at /home/openpower.student18/tmp/julia/src/gf.c:1851
jl_fptr_trampoline at /home/openpower.student18/tmp/julia/src/gf.c:1841
jl_apply_generic at /home/openpower.student18/tmp/julia/src/gf.c:2196
do_call at /home/openpower.student18/tmp/julia/src/interpreter.c:324
eval_value at /home/openpower.student18/tmp/julia/src/interpreter.c:430
eval_stmt_value at /home/openpower.student18/tmp/julia/src/interpreter.c:363 [inlined]
eval_body at /home/openpower.student18/tmp/julia/src/interpreter.c:684
jl_interpret_toplevel_thunk_callback at /home/openpower.student18/tmp/julia/src/interpreter.c:803
unknown function (ip: 0xfffffffffffffffe)
unknown function (ip: 0x7fff887a635f)
unknown function (ip: (nil))
jl_interpret_toplevel_thunk at /home/openpower.student18/tmp/julia/src/interpreter.c:812
jl_toplevel_eval at /home/openpower.student18/tmp/julia/src/toplevel.c:792
jl_toplevel_eval_in at /home/openpower.student18/tmp/julia/src/builtins.c:622
eval at ./boot.jl:319
jl_fptr_args at /home/openpower.student18/tmp/julia/src/gf.c:1851
jl_apply_generic at /home/openpower.student18/tmp/julia/src/gf.c:2196
eval_user_input at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/REPL/src/REPL.jl:85
macro expansion at /home/openpower.student18/tmp/julia/usr/share/julia/stdlib/v1.1/REPL/src/REPL.jl:117 [inlined]
#28 at ./task.jl:259
jl_fptr_args at /home/openpower.student18/tmp/julia/src/gf.c:1851
jl_apply_generic at /home/openpower.student18/tmp/julia/src/gf.c:2196
jl_apply at /home/openpower.student18/tmp/julia/src/julia.h:1558 [inlined]
start_task at /home/openpower.student18/tmp/julia/src/task.c:271
jl_set_base_ctx at /home/openpower.student18/tmp/julia/src/task.c:291
Allocations: 858046 (Pool: 857638; Big: 408); GC: 0
Segmentation fault

I will have access to this architecture (PPC64 little-endian) only until monday.

Issue 2:
From my investigations this is a null-pointer dereference, but not a usercode one.

I also observed other weird compilations that all included a ccall.

signal (11): Segmentation fault
in expression starting at no file:0
set_ssl_cert_locations at /buildworker/worker/package_linuxppc64le/build/usr/share/julia/stdlib/v0.7/LibGit2/src/error.jl:0
__init__ at /buildworker/worker/package_linuxppc64le/build/usr/share/julia/stdlib/v0.7/LibGit2/src/LibGit2.jl:990
jfptr___init___18949 at /buildworker/worker/package_linuxppc64le/build/usr/lib/julia/sys.so (unknown line)
jl_apply_generic at /buildworker/worker/package_linuxppc64le/build/src/gf.c:2167
jl_apply at /buildworker/worker/package_linuxppc64le/build/src/julia.h:1540 [inlined]
jl_module_run_initializer at /buildworker/worker/package_linuxppc64le/build/src/toplevel.c:90
_julia_init at /buildworker/worker/package_linuxppc64le/build/src/init.c:810
julia_init__threading at /buildworker/worker/package_linuxppc64le/build/src/task.c:302
main at /buildworker/worker/package_linuxppc64le/build/ui/repl.c:234
generic_start_main.isra.0 at /lib64/libc.so.6 (unknown line)
__libc_start_main at /lib64/libc.so.6 (unknown line)
Allocations: 5387 (Pool: 5378; Big: 9); GC: 0
make: *** [julia-base-cache] Segmentation fault (core dumped)