Original file line numberDiff line numberDiff line change@@ -61,7 +61,7 @@ jobs:
6161 || ''
6262 }}.txt handle_segv=0" >> "$GITHUB_ENV"
6363 else
64- echo "UBSAN_OPTIONS=${SAN_LOG_OPTION}" >> "$GITHUB_ENV"
64+ echo "UBSAN_OPTIONS=${SAN_LOG_OPTION} halt_on_error=1 suppressions=${GITHUB_WORKSPACE}/Tools/ubsan/suppressions.txt" >> "$GITHUB_ENV"
6565 fi
6666 echo "CC=clang" >> "$GITHUB_ENV"
6767 echo "CXX=clang++" >> "$GITHUB_ENV"
@@ -75,18 +75,21 @@ jobs:
7575 ${{
7676 inputs.sanitizer == 'TSan'
7777 && '--with-thread-sanitizer'
78- || '--with-undefined-behavior-sanitizer'
78+ || '--with-undefined-behavior-sanitizer --with-strict-overflow'
7979 }}
8080 --with-pydebug
8181 ${{ fromJSON(inputs.free-threading) && '--disable-gil' || '' }}
8282 - name: Build CPython
8383run: make -j4
8484 - name: Display build info
8585run: make pythoninfo
86+# test_{capi,faulthandler} are skipped under UBSan because
87+# they raise signals that UBSan with halt_on_error=1 intercepts.
8688 - name: Tests
8789run: >-
8890 ./python -m test
8991 ${{ inputs.sanitizer == 'TSan' && '--tsan' || '' }}
92+ ${{ inputs.sanitizer == 'UBSan' && '-x test_capi -x test_faulthandler' || '' }}
9093 -j4
9194 - name: Parallel tests
9295if: >-
Original file line numberDiff line numberDiff line change@@ -0,0 +1,28 @@
1+# This file contains suppressions for the UndefinedBehaviour sanitizer.
2+#
3+# Reference: https://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html#runtime-suppressions
4+#
5+# When adding a suppression, include a comment referencing a GitHub issue
6+# that describes how to reproduce the race and includes the relevant UBSan
7+# output.
8+9+# Objects/object.c:97:5: runtime error: member access within null pointer of type 'PyThreadState' (aka 'struct _ts')
10+null:Objects/object.c
11+12+# Objects/memoryobject.c:3032:15: runtime error: load of value 2, which is not a valid value for type 'bool'
13+bool:Objects/memoryobject.c
14+15+# Modules/_ctypes/cfield.c:644:1: runtime error: left shift of 1 by 63 places cannot be represented in type 'int64_t' (aka 'long')
16+shift-base:Modules/_ctypes/cfield.c
17+18+# Modules/_ctypes/cfield.c:640:1: runtime error: signed integer overflow: -2147483648 - 1 cannot be represented in type 'int'
19+signed-integer-overflow:Modules/_ctypes/cfield.c
20+21+# Modules/_zstd/decompressor.c:598:56: runtime error: applying non-zero offset 18446744073709551615 to null pointer
22+pointer-overflow:Modules/_zstd/decompressor.c
23+24+# Modules/_io/stringio.c:350:24: runtime error: addition of unsigned offset to 0x7fd01ec25850 overflowed to 0x7fd01ec2584c
25+pointer-overflow:Modules/_io/stringio.c
26+27+# Objects/bytesobject.c:1190:25: runtime error: applying zero offset to null pointer
28+pointer-overflow:Objects/bytesobject.c