diff options
| author | Robert Findley <rfindley@google.com> | 2022-02-02 13:47:31 -0500 |
|---|---|---|
| committer | Robert Findley <rfindley@google.com> | 2022-02-02 19:37:44 +0000 |
| commit | 77eff30ec0bc63df61ea742bb8278f92e2c133dc (patch) | |
| tree | 5d152782520da197733da353bcfa96e72955a78a /src | |
| parent | edbe4742a296239c06cd99721bb0dbc5008d35a1 (diff) | |
| download | go-77eff30ec0bc63df61ea742bb8278f92e2c133dc.tar.xz | |
go/types, types2: add a const to control recursion panics in unification
Add a panicAtUnificationDepthLimit const to replace the use of the debug
const to control whether to panic when the unification recursion depth
is reached. Our tests should pass when debug==true.
Change-Id: I58847f49d66010bd4ca01c0408ec10acac95cba6
Reviewed-on: https://go-review.googlesource.com/c/go/+/382534
Trust: Robert Findley <rfindley@google.com>
Run-TryBot: Robert Findley <rfindley@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Diffstat (limited to 'src')
| -rw-r--r-- | src/cmd/compile/internal/types2/unify.go | 14 | ||||
| -rw-r--r-- | src/go/types/unify.go | 14 |
2 files changed, 20 insertions, 8 deletions
diff --git a/src/cmd/compile/internal/types2/unify.go b/src/cmd/compile/internal/types2/unify.go index 13d5af671e..079db3276c 100644 --- a/src/cmd/compile/internal/types2/unify.go +++ b/src/cmd/compile/internal/types2/unify.go @@ -33,9 +33,15 @@ import ( // by setting up one of them (using init) and then assigning its value // to the other. -// Upper limit for recursion depth. Used to catch infinite recursions -// due to implementation issues (e.g., see issues #48619, #48656). -const unificationDepthLimit = 50 +const ( + // Upper limit for recursion depth. Used to catch infinite recursions + // due to implementation issues (e.g., see issues #48619, #48656). + unificationDepthLimit = 50 + + // Whether to panic when unificationDepthLimit is reached. Turn on when + // investigating infinite recursion. + panicAtUnificationDepthLimit = false +) // A unifier maintains the current type parameters for x and y // and the respective types inferred for each type parameter. @@ -244,7 +250,7 @@ func (u *unifier) nifyEq(x, y Type, p *ifacePair) bool { func (u *unifier) nify(x, y Type, p *ifacePair) bool { // Stop gap for cases where unification fails. if u.depth >= unificationDepthLimit { - if debug { + if panicAtUnificationDepthLimit { panic("unification reached recursion depth limit") } return false diff --git a/src/go/types/unify.go b/src/go/types/unify.go index 5d6d78bff0..be2037ca81 100644 --- a/src/go/types/unify.go +++ b/src/go/types/unify.go @@ -33,9 +33,15 @@ import ( // by setting up one of them (using init) and then assigning its value // to the other. -// Upper limit for recursion depth. Used to catch infinite recursions -// due to implementation issues (e.g., see issues #48619, #48656). -const unificationDepthLimit = 50 +const ( + // Upper limit for recursion depth. Used to catch infinite recursions + // due to implementation issues (e.g., see issues #48619, #48656). + unificationDepthLimit = 50 + + // Whether to panic when unificationDepthLimit is reached. Turn on when + // investigating infinite recursion. + panicAtUnificationDepthLimit = false +) // A unifier maintains the current type parameters for x and y // and the respective types inferred for each type parameter. @@ -244,7 +250,7 @@ func (u *unifier) nifyEq(x, y Type, p *ifacePair) bool { func (u *unifier) nify(x, y Type, p *ifacePair) bool { // Stop gap for cases where unification fails. if u.depth >= unificationDepthLimit { - if debug { + if panicAtUnificationDepthLimit { panic("unification reached recursion depth limit") } return false |