<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div dir="ltr">Thanks. I’m just trying to hack around the error:</div><div dir="ltr"><blockquote type="cite"><pre class="lang-cpp prettyprint prettyprinted" style="margin-top: 0px; margin-bottom: 1em; padding: 12px 8px; border: 0px; font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace, sans-serif; font-stretch: inherit; line-height: inherit; font-size: 13px; vertical-align: baseline; box-sizing: inherit; width: auto; max-height: 600px; overflow: auto; background-color: rgb(239, 240, 241); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; color: rgb(57, 51, 24); word-wrap: normal;"><code style="margin: 0px; padding: 0px; border: 0px; font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace, sans-serif; font-style: inherit; font-variant-caps: inherit; font-stretch: inherit; line-height: inherit; vertical-align: baseline; box-sizing: inherit; white-space: inherit;"><span class="typ" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant-caps: inherit; font-stretch: inherit; line-height: inherit; vertical-align: baseline; box-sizing: inherit; color: rgb(43, 145, 175);">Undefined</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant-caps: inherit; font-stretch: inherit; line-height: inherit; vertical-align: baseline; box-sizing: inherit; color: rgb(48, 51, 54);"> symbols </span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant-caps: inherit; font-stretch: inherit; line-height: inherit; vertical-align: baseline; box-sizing: inherit; color: rgb(16, 16, 148);">for</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-style: inherit; font-variant-caps: inherit; font-stretch: inherit; line-height: inherit; vertical-align: baseline; box-sizing: inherit; color: rgb(48, 51, 54);"> architecture x86_64</span></code></pre></blockquote></div><div dir="ltr"><br></div><div dir="ltr">Another possible solution is:</div><div dir="ltr"><blockquote type="cite"><span style="caret-color: rgb(36, 39, 41); color: rgb(36, 39, 41); font-family: Arial, "Helvetica Neue", Helvetica, sans-serif; font-size: 15px; background-color: rgb(255, 248, 220);">add -stdlib=libstdc++ to the linking command</span></blockquote></div><div dir="ltr"><br></div><div dir="ltr">See: https://stackoverflow.com/questions/19637164/c-linking-error-after-upgrading-to-mac-os-x-10-9-xcode-5-0-1</div><div dir="ltr"><br></div><div dir="ltr">I’ll try both, and go with the least-yuck one that works.</div><div dir="ltr"><br></div><div dir="ltr">What’s the Portfile directive to add -stdlib=libstdc++ to the linker?</div><div dir="ltr"><br></div><div dir="ltr"><blockquote type="cite">On Nov 21, 2019, at 19:46, Joshua Root <jmr@macports.org> wrote:<br><br></blockquote></div><blockquote type="cite"><div dir="ltr"><span>On 2019-11-22 09:35 , Steven Smith wrote:</span><blockquote type="cite"><span>CC=/usr/bin/clang++</span><br></blockquote><blockquote type="cite"><span></span><br></blockquote><blockquote type="cite"><span></span><br></blockquote><blockquote type="cite"><span>Error on the Mac: Undefined symbols for architecture x86_64 · Issue #285 · nlohmann/json</span><br></blockquote><blockquote type="cite"><span>https://github.com/nlohmann/json/issues/285#issuecomment-348090484</span><br></blockquote><span></span><br><span>Is the build system really using $CC to compile C++ code? The usual</span><br><span>convention is that CC is the C compiler and CXX is the C++ compiler.</span><br><span>Naturally using the wrong one will cause problems.</span><br><span></span><br><span>Sticking to the convention is greatly preferable, but if for some reason</span><br><span>you really need to name a C++ compiler in CC, this will do it:</span><br><span></span><br><span># Yuck</span><br><span>configure.cc ${configure.cxx}</span><br><span></span><br><span>- Josh</span><br></div></blockquote></body></html>