1. A method of making secure the execution of a computer program (EXE) in a computing device comprising a microprocessor, the method comprising: a first step (E 30 ), performed prior to the execution of the computer program, of calculating and storing, into a first read-only memory readable by the microprocessor, a first signature (SIG 1 ) representative of the intended execution of a set of instructions of the computer program (EXE), said calculating being carried out according to a predetermined calculation mode; a second step, following said first step (E 30 ), of executing the set of instructions of the computer program by way of the microprocessor, said second step (E 50 ) including calculating, performed as a result of the execution of the set of instructions, a second signature (SIG 2 ) representative of the execution of the set of instructions of the computer program, and storing said second signature (SIG 2 ) in a writeable memory readable by said microprocessor; and a third step (E 60 ) of reading the first signature (SIG 1 ) stored in the first read-only memory and the second signature (SIG 2 ) stored in the writeable memory for determining an existence of an anomaly in the execution of the set of instructions, wherein the set of instructions of the computer program (EXE) are recorded in any of the first or a second read-only memory readable by the microprocessor, and wherein the instructions for making the execution of the computer program (EXE) secure, compiled from source code and included in the set of instructions of the computer program (EXE) and recorded in the read-only memory to be read and executed by said microprocessor, comprise at least one first instruction that initializes said step (E 50 ) of calculating and storing the second signature, at least one second instruction for performing the step of calculating and storing the second signature consistent with the calculation mode of the first signature, a third instruction, different from said at least one second instruction, that compares the second signature obtained according to the at least one second instruction with the first signature, and a fourth instruction that manages an execution anomaly detected in response to the comparing of the second signature with the first signature.