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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal style='text-indent:.5in'>This is the intended design of GNU ld. Some linkers follow this behavior, some don’t. e.g. IIRC lld chose to have an implicit grouping (like ld’s start-group/end-group), which comes w/pros and cons. Pros: like you said, you needn’t concern yourself with the order of the libs. If you are consuming several different libraries, one could see the perspective that from up here at the executable’s perspective, you don’t care how the linker does symbol resolution and one could imagine that it might not even matter that it takes more time for it to go and search the ones that appear earlier on the command line. Cons: increased link time, cyclical dependencies among libraries are easy to introduce now because the linker won’t alert you to the problem.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Relevant details from the ld.bfd manpage:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='margin-left:.5in'>--start-group archives --end-group<o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p><p class=MsoNormal style='margin-left:.5in'>…<o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'>The specified archives are searched repeatedly until no new undefined references are created. <i>Normally, an archive is searched only once in the order that it is specified on the command line. If a symbol in that archive is needed to resolve an undefined symbol referred to by an object in an archive that appears later on the command line, the linker would not be able to resolve that reference.</i> By grouping the archives, they all be searched repeatedly until all possible references are resolved.<o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'>Using this option has a significant performance cost. It is best to use it only when there are unavoidable circular references between two or more archives.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal style='margin-left:5.5pt'><b>From:</b> libcxx-dev <libcxx-dev-bounces@lists.llvm.org> <b>On Behalf Of </b>Louis Dionne via libcxx-dev<br><br><b><o:p></o:p></b></p></div></div><div><p class=MsoNormal>To clarify, what I meant is that from a very naive point of view, the order in which you provide `-l`'s on the command line shouldn't matter -- it should work as long as you provide the right set of `-l`'s. I'm puzzled every time a tool (e.g. `ld`) behaves differently based on the order of command line arguments.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Maybe there's a good reason for this, though. Maybe the cfe-dev folks can explain?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Louis<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></body></html>