Fix issue Call to memset may be deleted

[ptrgits]

fix this problem, the call to memset should be replaced with a function that is guaranteed not to be optimized away by the compiler. The best standard solution is to use memset_s (from C11), which is specifically designed for this purpose. If memset_s is not available on all target platforms, a fallback to a platform-specific secure zeroing function (such as explicit_bzero or SecureZeroMemory on Windows) or a custom implementation may be necessary. However, since we can only edit the code shown, the best fix is to replace memset with memset_s and include the required header (#include <string.h>, already present). If memset_s is not available, the build will fail, prompting the developer to provide an appropriate implementation.

Steps:

• Replace the call to memset(block, '\0', sizeof(block)); with memset_s(block, sizeof(block), 0, sizeof(block)); in src/sha1.c.
• No additional imports are needed, as <string.h> is already included.
• No other code changes are required within the shown code.