Improved variable-pitch stator and method for using such a stator

A turbomachine stator extending about a central axis and comprising:

• an inner wall and an outer wall delimiting an annular flow passage, a plurality of variable-pitch vanes, each vane extending radially in the annular flow passage between a base movably fixed to one of the inner wall or of the outer wall, and a free end,
• the other of the inner wall or of the outer wall comprising a main profile and at least one circular platform arranged opposite the free end of one of the vanes, the platform comprising a main surface and at least one longitudinal groove, the platform being movable in rotation relative to the main profile between a first position in which a main axis of the groove is substantially parallel to the central axis, and at least a second position in which the main axis is transverse to the central axis.