Even if you're OK with breaking every call to malloc(), as the other poster said, plenty of C code has variables named things that clash with C++ reserved words

Even if you're OK with breaking every call to malloc(), as the other poster said, plenty of C code has variables named things that clash with C++ reserved words, such as new, and, while it's possible for programming languages to simply not have reserved words, I think C++ implementation developers and programmers would rather avoid the kinds of things clever C++ programmers would come up with were those guide rails to be taken off. https://softwareengineering.stackexchange.com/questions/189699/what-non-theoretical-practical-programming-language-has-no-reserved-keywords https://softwareengineering.stackexchange.com/questions/1896... No reserved words in PL/I: https://www.ibm.com/docs/en/epfz/5.3?topic=sbcs-identifiers https://www.ibm.com/docs/en/epfz/5.3?topic=sbcs-identifiers > Identifiers can be PL/I keywords or programmer-defined names. Because PL/I can determine from the context if an identifier is a keyword, you can use any identifier as a programmer-defined name. There are no reserved words in PL/I. However, using some keywords, for example, IF or THEN, as variable names might make a program needlessly hard to understand.