Compilation failure with `-O0` + `-fsanitize=address` due to inline asm

achow101 commented at 3:49 pm on April 3, 2024: member

Is there an existing issue for this?

I have searched the existing issues

Current behaviour

Configure with

0./configure --enable-fuzz --enable-debug --with-sanitizers=address,fuzzer,undefined,integer CC=clang CXX=clang++

Compile fails:

 0crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
 1   44 |         "shl    $0x6,%2;"
 2      |         ^
 3<inline asm>:1:1882: note: instantiated into assembly here
 4crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
 5   44 |         "shl    $0x6,%2;"
 6      |         ^
 7<inline asm>:1:2591: note: instantiated into assembly here
 8crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
 9   44 |         "shl    $0x6,%2;"
10      |         ^
11<inline asm>:1:3284: note: instantiated into assembly here
12crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
13   44 |         "shl    $0x6,%2;"
14      |         ^
15<inline asm>:1:4686: note: instantiated into assembly here
16crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
17   44 |         "shl    $0x6,%2;"
18      |         ^
19<inline asm>:1:5395: note: instantiated into assembly here
20crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
21   44 |         "shl    $0x6,%2;"
22      |         ^
23<inline asm>:1:6088: note: instantiated into assembly here
24crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
25   44 |         "shl    $0x6,%2;"
26      |         ^
27<inline asm>:1:7490: note: instantiated into assembly here
28crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
29   44 |         "shl    $0x6,%2;"
30      |         ^
31<inline asm>:1:8199: note: instantiated into assembly here
32crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
33   44 |         "shl    $0x6,%2;"
34      |         ^
35<inline asm>:1:8892: note: instantiated into assembly here
36crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
37   44 |         "shl    $0x6,%2;"
38      |         ^
39<inline asm>:1:10312: note: instantiated into assembly here
40crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
41   44 |         "shl    $0x6,%2;"
42      |         ^
43<inline asm>:1:11021: note: instantiated into assembly here
44crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
45   44 |         "shl    $0x6,%2;"
46      |         ^
47<inline asm>:1:11714: note: instantiated into assembly here
48crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
49   44 |         "shl    $0x6,%2;"
50      |         ^
51<inline asm>:1:12859: note: instantiated into assembly here
52crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
53   44 |         "shl    $0x6,%2;"
54      |         ^
55<inline asm>:1:13356: note: instantiated into assembly here
56crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
57   44 |         "shl    $0x6,%2;"
58      |         ^
59<inline asm>:1:13853: note: instantiated into assembly here
60crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
61   44 |         "shl    $0x6,%2;"
62      |         ^
63<inline asm>:1:14900: note: instantiated into assembly here
64crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
65   44 |         "shl    $0x6,%2;"
66      |         ^
67<inline asm>:1:15397: note: instantiated into assembly here
68crypto/sha256_sse4.cpp:44:9: error: expected relocatable expression
69   44 |         "shl    $0x6,%2;"
70      |         ^
71<inline asm>:1:15894: note: instantiated into assembly here
7218 errors generated.
73make[2]: *** [Makefile:14531: crypto/libbitcoin_crypto_base_la-sha256_sse4.lo] Error 1

Expected behaviour

It should successfully compile with the debug symbols so that fuzz crashes can be debugged.

Previously, it was possible to work around this issue by using --disable-asm however that was removed in #29407

Steps to reproduce

See above configure .

--enable-debug and --enable-fuzz individually do not result in compilation failure. I am only seeing this when using them together.

Relevant log output

config.log

How did you obtain Bitcoin Core

Compiled from source

What version of Bitcoin Core are you using?

master@0d509bab45d292caeaf34600e57b5928757c6005

Operating system and version

Arch w/ linux kernel 6.8.2

Machine specifications

No response

maflcko commented at 3:56 pm on April 3, 2024: member

Recalling the IRC discussion, I presume this happens since -O0 in #16435 ?

maflcko added the label Build system on Apr 3, 2024

maflcko added the label Tests on Apr 3, 2024

maflcko commented at 4:00 pm on April 3, 2024: member

Ref:

01802024-04-01T18:09:22  <cfields> clang++ -std=c++20 -O0 -fsanitize=address -c crypto/sha256_sse4.cpp -o out.o

https://www.erisian.com.au/bitcoin-core-dev/log-2024-04-02.html

fanquake commented at 4:00 pm on April 3, 2024: member

The broken combination is clang++ -std=c++20 -O0 -fsanitize=address -c crypto/sha256_sse4.cpp -o out.o, pointed out by Cory. Happens for me with Clang-18.

fanquake removed the label Build system on Apr 3, 2024

fanquake added the label Upstream on Apr 3, 2024

fanquake commented at 4:03 pm on April 3, 2024: member

I guess the next step is to followup / file an issue with LLVM. I’ve got #29796 open which may “fix” this by just dropping -O0, depending on the outcome of discussion.

jonatack commented at 5:28 pm on April 3, 2024: contributor

FWIW, unable to reproduce on arm64 macOS 14.4.1 with Homebrew clang 17.0.6.

maflcko commented at 6:02 pm on April 3, 2024: member

It only happens on x86-64, because the asm is in that format.

theuni commented at 8:05 pm on April 3, 2024: member

In addition to the discussion in #29781, I’ll PR a change to make this work with DISABLE_OPTIMIZED_SHA256 as a fallback. I’m doing that as part of a larger refactor of the crypto defines, though.

fanquake renamed this:
~~Compilation failure when using `--enable-fuzz` and `--enable-debug` due to inline asm~~
Compilation failure with `-O0` + `-fsanitize=address` due to inline asm
on Apr 6, 2024

ajtowns commented at 8:56 am on May 13, 2024: contributor

How about adding something like:

 0--- a/configure.ac
 1+++ b/configure.ac
 2@@ -349,7 +349,14 @@ esac
 3 if test "$enable_debug" = "yes"; then
 4 
 5   dnl Disable all optimizations
 6-  AX_CHECK_COMPILE_FLAG([-O0], [DEBUG_CXXFLAGS="$DEBUG_CXXFLAGS -O0"], [], [$CXXFLAG_WERROR])
 7+  case "$use_sanitizers" in
 8+    *address*)
 9+      AX_CHECK_COMPILE_FLAG([-Og], [DEBUG_CXXFLAGS="$DEBUG_CXXFLAGS -Og"], [], [$CXXFLAG_WERROR])
10+      ;;
11+    *)
12+      AX_CHECK_COMPILE_FLAG([-O0], [DEBUG_CXXFLAGS="$DEBUG_CXXFLAGS -O0"], [], [$CXXFLAG_WERROR])
13+      ;;
14+  esac

in the meantime?

theuni commented at 6:17 pm on May 13, 2024: member

@ajtowns Thanks for the reminder here. See #30097 for a function-level application (kinda :) of the above.

fanquake closed this on May 16, 2024

fanquake referenced this in commit ae2658caac on May 16, 2024

Compilation failure with -O0 + -fsanitize=address due to inline asm #29801