Hi,
In making some edits to the file mentioned in the subject line, I stumbled upon something that kept me occupied for way longer than I care to admit.
I believe that it will prove to be readily reproducible, but I'd be delighted if that turns out to *not* be the case.
Please feel free to test this.

In this ListUtil.xs you will find the following: 
Line 1193:                sv_setpvf(keysv, "%.15" NVgf, SvNV(arg));
Line 1194:#ifdef HV_FETCH_EMPTY_HE

[download]
I find that the code becomes uncompilable if I insert an empty line between those 2 lines: 
Line 1193:                sv_setpvf(keysv, "%.15" NVgf, SvNV(arg));
Line 1194:
Line 1195:#ifdef HV_FETCH_EMPTY_HE

[download]
On both Ubuntu and MS Windows (perl-5.30.0 and others) that modification quickly produces the following error (during the 'make' stage of the build): 
Code is not inside a function (maybe last function was ended by a blan
+k line followed by a statement on column one?) in ListUtil.xs, line 1
+195
Makefile:360: recipe for target 'ListUtil.c' failed

[download]
Can someone explain that behaviour to me ?
Are XS files typically that sensitive to white space ? (I've struck nothing like it before.)

Cheers
Rob

In reply to Puzzled by the ListUtil.xs in Scalar-List-Utils-1.52.tar.gz by syphilis

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