Runtime errors and warning that occur in the elsif condition were reported as being on the line of the "if".

>perl580\bin\perl -we"if ( $foo ) {}" -e "elsif ( length($bar) ) {}"
Name "main::bar" used only once: possible typo at -e line 2.
Name "main::foo" used only once: possible typo at -e line 1.
Use of uninitialized value in length at -e line 1.
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I don't know about 5.8.7, but it's was fixed by 5.8.8.

>perl588\bin\perl -we"if ( $foo ) {}" -e "elsif ( length($bar) ) {}"
Name "main::bar" used only once: possible typo at -e line 2.
Name "main::foo" used only once: possible typo at -e line 1.
Use of uninitialized value in length at -e line 2.
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In any case, that's not the problem here since the if in question doesn't have an elsif clause.