Is it OK to short-circuit the outputs of multiple general-purpose CMOS logic ICs?
Wired-OR logic in which multiple outputs are connected together is prohibited because they are short-circuited. Obviously, any output must not be connected to Vcc or GND.
Multiple gates in the same package can be connected together as shown below to increase the drive capability.
However, it is recommended to use high-drive ICs instead, such as the 74AC, 74LCX and 74VCX series.
[Figure: Examples of prohibited wired-OR connections and increasing drive capabilities]