Ensure SIZE_MAX can be used throughout our code.

Pre-C99 platforms may lack <stdint.h> and thereby SIZE_MAX.  We have
a couple of places using the hack "(size_t) -1" as a fallback, but
it wasn't universally available; which means the code added in commit
2e70d6b5e fails to compile everywhere.  Move that hack to c.h so that
we can rely on having SIZE_MAX everywhere.

Per discussion, it'd be a good idea to make the macro's value safe
for use in #if-tests, but that will take a bit more work.  This is
just a quick expedient to get the buildfarm green again.

Back-patch to all supported branches, like the previous commit.

Discussion: https://postgr.es/m/15883.1504278595@sss.pgh.pa.us
This commit is contained in:
Tom Lane 2017-09-01 13:52:54 -04:00
parent 2338ad2637
commit 9a98557662
3 changed files with 5 additions and 5 deletions

View File

@ -288,6 +288,10 @@ typedef unsigned long long int uint64;
#define UINT64CONST(x) ((uint64) x)
#endif
/* Max value of size_t might be missing if we don't have stdint.h */
#ifndef SIZE_MAX
#define SIZE_MAX ((size_t) -1)
#endif
/* Select timestamp representation (float8 or int64) */
#ifdef USE_INTEGER_DATETIMES

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@ -41,7 +41,7 @@
#define AllocSizeIsValid(size) ((Size) (size) <= MaxAllocSize)
#define MaxAllocHugeSize ((Size) -1 >> 1) /* SIZE_MAX / 2 */
#define MaxAllocHugeSize (SIZE_MAX / 2)
#define AllocHugeSizeIsValid(size) ((Size) (size) <= MaxAllocHugeSize)

View File

@ -48,10 +48,6 @@
/* Unlike <ctype.h>'s isdigit, this also works if c < 0 | c > UCHAR_MAX. */
#define is_digit(c) ((unsigned)(c) - '0' <= 9)
#ifndef SIZE_MAX
#define SIZE_MAX ((size_t) -1)
#endif
/*
* SunOS 4.1.1 libraries lack remove.
*/