diff options
| -rw-r--r-- | lib/system/assign.nim | 8 | ||||
| -rw-r--r-- | tests/objects/t20972.nim | 15 |
2 files changed, 20 insertions, 3 deletions
diff --git a/lib/system/assign.nim b/lib/system/assign.nim index 42587929c..9f4cbc0fe 100644 --- a/lib/system/assign.nim +++ b/lib/system/assign.nim @@ -275,10 +275,12 @@ proc genericReset(dest: pointer, mt: PNimType) = proc selectBranch(discVal, L: int, a: ptr array[0x7fff, ptr TNimNode]): ptr TNimNode = - result = a[L] # a[L] contains the ``else`` part (but may be nil) if discVal <% L: - let x = a[discVal] - if x != nil: result = x + result = a[discVal] + if result == nil: + result = a[L] + else: + result = a[L] # a[L] contains the ``else`` part (but may be nil) proc FieldDiscriminantCheck(oldDiscVal, newDiscVal: int, a: ptr array[0x7fff, ptr TNimNode], diff --git a/tests/objects/t20972.nim b/tests/objects/t20972.nim new file mode 100644 index 000000000..6383dc9b1 --- /dev/null +++ b/tests/objects/t20972.nim @@ -0,0 +1,15 @@ +discard """ + matrix: "--mm:refc -d:release; --mm:orc -d:release" +""" + +{.passC: "-fsanitize=undefined -fsanitize-undefined-trap-on-error -Wall -Wextra -pedantic -flto".} +{.passL: "-fsanitize=undefined -fsanitize-undefined-trap-on-error -flto".} + +# bug #20972 +type ForkedEpochInfo = object + case kind: bool + of true, false: discard +var info = ForkedEpochInfo(kind: true) +doAssert info.kind +info.kind = false +doAssert not info.kind |