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Diffstat (limited to 'doc/manual.cli')
| -rw-r--r-- | doc/manual.cli | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/doc/manual.cli b/doc/manual.cli index c966cfd..c7eef38 100644 --- a/doc/manual.cli +++ b/doc/manual.cli @@ -2902,7 +2902,16 @@ recursively. And when the library is installed, this information is carried over to its \c{pkg-config(1)} file. \N|Similar to the \c{c.*} and \c{cc.*} sets discussed earlier, there are also -\c{c.export.*} and \c{cc.export.*} sets.| +\c{c.export.*} and \c{cc.export.*} sets. + +Note, however, that there is no \c{*.export.coptions} since a library imposing +compilation options on its consumers is bad practice (too coarse-grained, does +not compose, etc). Instead, the recommended approach is to specify in the +library documentation that it expects its consumers to use a certain +compilation option. And if your library is unusable without exporting a +compilation option and you are sure benefits outweigh the drawbacks, then you +can specify it as part of \c{*.export.poptions} (it is still a good idea to +prominently document this).| Here are the parts relevant to the library metadata protocol in the above \c{buildfile}: @@ -3000,7 +3009,12 @@ memory. Note also that this only applies to shared libraries. In case of static libraries, both interface and implementation dependencies are always linked, -recursively.| +recursively. Specifically, when linking a shared library, only libraries +specified in its \c{*.export.libs} are linked. While when linking a static +library, all its library prerequisites as well as those specified in +\c{*.libs} are linked. Note that \c{*.export.libs} is not used when linking a +static library since it is naturally assumed that all such libraries are also +specified as library prerequisites or in \c{*.libs}.| The remaining lines in the library metadata fragment are: @@ -3059,6 +3073,16 @@ a binary-ful (\i{binful}) shared variants. Note also that binless libraries can depend on binful libraries and are fully supported where the \c{pkg-config(1)} functionality is concerned. +One counter-intuitive aspect of having a binless library that depends on a +system binful library, for example, \c{-lm}, is that you still have to specify +the system library in both \c{*.export.libs} and \c{*.libs} because the latter +is used when linking the static variant of the binless library. For example: + +\ +cxx.libs = -lm +lib{hello}: cxx.export.libs = -lm +\ + If you are creating a new library with \l{bdep-new(1)} and are certain that it will always be binless and in all configurations, then you can produce a simplified \c{buildfile} by specifying the \c{binless} option, for example: |