Request for review: 7102489: RFE: cleanup jlong typedef on __APPLE__ and _LP64 systems

David Holmes david.holmes at
Sat Jan 12 15:05:37 PST 2013

Sorry Harold I didn't see this before my other reply. Now I understand 
your problem. We either have to:

a) typedef long long jlong on all platforms; or
b) special case the typedef for jlong on Apple; or
c) special case the typedef for JLONG_FORMAT on Apple

But even if we do (a) any platform that defines int64_t differently to 
our jlong will mean we still need distinct format specifiers. Further 
unless we know how int64_t is defined on a given platform we don't know 
what format specifier to use (%ld or %lld).

Do compilers that provide things like int64_t also define a format 
specifier macro?


On 12/01/2013 12:36 AM, harold seigel wrote:
> Hi Vladimir,
> Thank you for your comments.  Mac OS defines int64_t as 'long long'.
> So, int64_t needs a different format specifier than jlong, which this
> fix now defines as 'long'.  This is because, as shown below, the Mac OS
> C++ compiler is picky about format specifiers for values of types 'long
> long' and 'long'.
>     $ gcc lld.cpp
>     lld.cpp: In function int main(int, char**):
>     lld.cpp:8: warning: format %lld expects type long long int, but
>     argument 2 has type long int
>     lld.cpp:9: warning: format %ld expects type long int, but argument 2
>     has type int64_t
>     $ cat lld.cpp
>     #include <stdio.h>
>     #include <stdint.h>
>     int main(int argc, char * argv[]) {
>        long long_val = 5;
>        int64_t int64_val = 8;
>        printf("long_val: %ld\n", long_val);
>        printf("long_val: %lld\n", long_val); <---- Line 8
>        printf("int64_val: %ld\n", int64_val); <--- Line 9
>        printf("int64_val: %lld\n", int64_val);
>        return 0;
>     }
> That is why I added JLONG_FORMAT.
> Thanks, Harold
> On 1/10/2013 9:46 PM, Vladimir Kozlov wrote:
>> Can we just define INT64_FORMAT as platform specific and use it
>> instead of adding new JLONG_FORMAT?
>> Thanks,
>> Vladimir
>> On 1/10/13 10:39 AM, harold seigel wrote:
>>> Hi,
>>> Please review the following changes to fix bug 7102489.
>>> Summary:
>>> The definition of type jlong differed on Mac OS from the other 64 bit
>>> platforms.  This fix makes it consistent.  In order to do this, this fix
>>> defines new macros, JLONG_FORMAT and JULONG_FORMAT, for printing and
>>> scanning jlongs and julongs.
>>> This fix also does some cleanup.  Methods jlong_format_specifier() and
>>> julong_format_specifer() were removed and some format specifiers were
>>> replaced with appropriate macros.
>>> Open webrev at
>>> <>
>>> Bug link at
>>> Thank you,
>>> Harold

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