diff options
| author | Thomas Munro | 2022-12-22 04:14:23 +0000 |
|---|---|---|
| committer | Thomas Munro | 2022-12-22 05:32:10 +0000 |
| commit | 3f28bd7337d7c01820283fee51027a9dc9d2295f (patch) | |
| tree | 504103a001fac55d82ea258352c1e9c5490f08fc | |
| parent | 01be9d498fa4b836ec3dbf035b6743c8b8f34767 (diff) | |
Add work-around for VA_ARGS_NARGS() on MSVC.
The previous coding of VA_ARGS_NARGS() always returned 1 on Visual
Studio, because it treats __VA_ARGS__ as a single token unless you jump
through extra hoops. Newer compilers have an option to fix that. Add a
comment about that so that we can remember to clean this up in the
future when our minimum MSVC version advances.
Author: Victor Spirin <[email protected]>
Reviewed-by: Thomas Munro <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Reviewed-by: Michael Paquier <[email protected]>
Discussion: https://postgr.es/m/f450fc57-a147-19d0-e50c-33571c52cc13%40postgrespro.ru
| -rw-r--r-- | src/include/c.h | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/src/include/c.h b/src/include/c.h index bd6d8e5bf5..7567ef7888 100644 --- a/src/include/c.h +++ b/src/include/c.h @@ -324,7 +324,25 @@ * pretty trivial: VA_ARGS_NARGS_() returns its 64th argument, and we set up * the call so that that is the appropriate one of the list of constants. * This idea is due to Laurent Deniau. + * + * MSVC has an implementation of __VA_ARGS__ that doesn't conform to the + * standard unless you use the /Zc:preprocessor compiler flag, but that + * isn't available before Visual Studio 2019. For now, use a different + * definition that also works on older compilers. */ +#ifdef _MSC_VER +#define EXPAND(args) args +#define VA_ARGS_NARGS(...) \ + VA_ARGS_NARGS_ EXPAND((__VA_ARGS__, \ + 63,62,61,60, \ + 59,58,57,56,55,54,53,52,51,50, \ + 49,48,47,46,45,44,43,42,41,40, \ + 39,38,37,36,35,34,33,32,31,30, \ + 29,28,27,26,25,24,23,22,21,20, \ + 19,18,17,16,15,14,13,12,11,10, \ + 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)) +#else + #define VA_ARGS_NARGS(...) \ VA_ARGS_NARGS_(__VA_ARGS__, \ 63,62,61,60, \ @@ -334,6 +352,8 @@ 29,28,27,26,25,24,23,22,21,20, \ 19,18,17,16,15,14,13,12,11,10, \ 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) +#endif + #define VA_ARGS_NARGS_( \ _01,_02,_03,_04,_05,_06,_07,_08,_09,_10, \ _11,_12,_13,_14,_15,_16,_17,_18,_19,_20, \ |