clangupc2c defines __GCC_UPC__ about clang-upc HOT 2 CLOSED

It does make sense to drop GCC_UPC from the Clang UPC.

I would also add CLANG_UPC but it was pointed to me that both CLANG_UPC and GCC_UPC are probably not be needed. Definitions of GNUC and UPC has the same meaning as GCC_UPC, and clang can differentiate between GUCP and Clang UPC.

from clang-upc.

I would also add CLANG_UPC but it was pointed to me that both CLANG_UPC and GCC_UPC are probably not be needed.

I disagree since the Berkeley translator can (and will) define __UPC__ and one or both of __GNUC__ and __clang__. That means __UPC__ && __clang__ is ambiguous (could be BUPC or clang-upc[2c]), and __UPC__ && __GNUC__ can be true for any of the three current translator/compiler choice supported by the upcc driver.

Summary, from the point of view of the guy maintaining UPCR, the test harness and the upcc driver:

• Berkeley translator defines __UPC__ and __BERKELEY_UPC__, maybe defines __GNUC__ and/or __clang__
• GUPC defines __UPC__, __GUPC__, and __GCC_UPC__
• Clang-upc2c defines __UPC__ and __clang__, maybe defines __GNUC__

The main complication is that depending on the backend compiler in use the Berkeley and upc2c translator cases may define __GNUC__ and the Berkeley translator might also define __clang__

So, the "canonical" ID formulae if one removes __GCC_UPC__ but does not add __CLANG_UPC__:

• Berkeley: #if defined(__BERKELEY_UPC__)
• GUPC: #if defined(_GCC_UPC__)
• clang-upc[2c]: #if defined(__UPC__) && defined(__clang__) && !defined(__BERKELEY_UPC__)

I am OK with needing defined(__UPC__) && defined(__clang__) to distinguish clang-upc2c, but really dislike the need for && !defined(__BERKELEY_UPC__) to avoid confusion in the case of BUPC with CC=clang. On this basis, I would still like to see a definition of __CLANG_UPC__. However, I am fully prepared to add -D__CLANG_UPC__=1 within the upcc driver if you guys would rather not make it predefined within clang-upc[2c]. Just say so and I'll use that approach and drop my request to see it predefined by clang-upc.

from clang-upc.