Description:
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When running php from another path the extensions cannot be loaded in alpha3 if extension_dir is a relative path (extension_dir = "ext"). This works in all versions before.

Test script:
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When calling this in a CMD window:

    C:\Sandbox\tests\php7.2-bug>c:\php\7.2.0alpha3-nts\php test2.php

Several warnings will arise because libraries cannot be loaded.

When calling the script the other way round the extensions are loaded without a problem:

    C:\php\7.2.0alpha3-nts>php c:\Sandbox\tests\php7.2-bug\test2.php



Actual result:
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PHP Warning:  Cannot access dynamic library 'gd2' (tried : ext\gd2, ext\php_gd2.dll) in Unknown on line 0

Warning: Cannot access dynamic library 'gd2' (tried : ext\gd2, ext\php_gd2.dll) in Unknown on line 0
...