diff options
Diffstat (limited to 'Source/cmTarget.cxx')
| -rw-r--r-- | Source/cmTarget.cxx | 80 |
1 files changed, 65 insertions, 15 deletions
diff --git a/Source/cmTarget.cxx b/Source/cmTarget.cxx index d3f2726..9142f1f 100644 --- a/Source/cmTarget.cxx +++ b/Source/cmTarget.cxx @@ -139,6 +139,32 @@ bool cmTarget::HasCxx() const void cmTarget::AnalyzeLibDependencies( const cmMakefile& mf ) { + // There are two key parts of the dependency analysis: (1) + // determining the libraries in the link line, and (2) constructing + // the dependency graph for those libraries. + // + // The latter is done using the cache entries that record the + // dependencies of each library. + // + // The former is a more thorny issue, since it is not clear how to + // determine if two libraries listed on the link line refer to the a + // single library or not. For example, consider the link "libraries" + // /usr/lib/libtiff.so -ltiff + // Is this one library or two? The solution implemented here is the + // simplest (and probably the only practical) one: two libraries are + // the same if their "link strings" are identical. Thus, the two + // libraries above are considered distinct. This also means that for + // dependency analysis to be effective, the CMake user must specify + // libraries build by his project without using any linker flags or + // file extensions. That is, + // LINK_LIBRARIES( One Two ) + // instead of + // LINK_LIBRARIES( -lOne ${binarypath}/libTwo.a ) + // The former is probably what most users would do, but it never + // hurts to document the assumptions. :-) Therefore, in the analysis + // code, the "canonical name" of a library is simply its name as + // given to a LINK_LIBRARIES command. + typedef std::vector< std::string > LinkLine; // Maps the canonical names to the full objects of m_LinkLibraries. @@ -146,7 +172,8 @@ cmTarget::AnalyzeLibDependencies( const cmMakefile& mf ) // The unique list of libraries on the orginal link line. They // correspond to lib_map keys. However, lib_map will also get - // further populated by the dependency analysis. + // further populated by the dependency analysis, while this will be + // unchanged. LinkLine orig_libs; // The list canonical names in the order they were orginally @@ -156,6 +183,10 @@ cmTarget::AnalyzeLibDependencies( const cmMakefile& mf ) // The dependency maps. DependencyMap dep_map, dep_map_implicit; + + // 1. Determine the list of unique libraries in the original link + // line. + LinkLibraries::iterator lib; for(lib = m_LinkLibraries.begin(); lib != m_LinkLibraries.end(); ++lib) { @@ -163,7 +194,7 @@ cmTarget::AnalyzeLibDependencies( const cmMakefile& mf ) // if a variable expands to nothing. if (lib->first.size() == 0) continue; - std::string cname = lib->first; + const std::string& cname = lib->first; lib_order.push_back( cname ); if( lib_map.end() == lib_map.find( cname ) ) { @@ -172,11 +203,18 @@ cmTarget::AnalyzeLibDependencies( const cmMakefile& mf ) } } + // 2. Gather the dependencies. + + // If LIBRARY_OUTPUT_PATH is not set, then we must add search paths + // for all the new libraries added by the dependency analysis. + const char* libOutPath = mf.GetDefinition("LIBRARY_OUTPUT_PATH"); + bool addLibDirs = (libOutPath==0 || strcmp(libOutPath,"")==0); + // First, get the explicit dependencies for those libraries that - // have specified them + // have specified them. for( LinkLine::iterator i = orig_libs.begin(); i != orig_libs.end(); ++i ) { - this->GatherDependencies( mf, *i, dep_map, lib_map ); + this->GatherDependencies( mf, *i, dep_map, lib_map, addLibDirs ); } // For the rest, get implicit dependencies. A library x depends @@ -216,7 +254,10 @@ cmTarget::AnalyzeLibDependencies( const cmMakefile& mf ) dep_map[ i->first ] = i->second; } - // Create a new link line order. + // 3. Create a new link line, trying as much as possible to keep the + // original link line order. + + // Get the link line as canonical names. std::set<std::string> done, visited; std::vector<std::string> link_line; for( LinkLine::iterator i = orig_libs.begin(); i != orig_libs.end(); ++i ) @@ -224,19 +265,14 @@ cmTarget::AnalyzeLibDependencies( const cmMakefile& mf ) Emit( *i, dep_map, done, visited, link_line ); } - - // If LIBRARY_OUTPUT_PATH is not set, then we must add search paths - // for all the new libraries added by the dependency analysis. - const char* libOutPath = mf.GetDefinition("LIBRARY_OUTPUT_PATH"); - bool addLibDirs = (libOutPath==0 || strcmp(libOutPath,"")==0); + // Translate the canonical names into internal objects. m_LinkLibraries.clear(); for( std::vector<std::string>::reverse_iterator i = link_line.rbegin(); i != link_line.rend(); ++i ) { // Some of the libraries in the new link line may not have been in // the orginal link line, but were added by the dependency - // analysis. For these libraries, we assume the GENERAL type and - // add the name of the library. + // analysis. if( lib_map.find(*i) == lib_map.end() ) { if( addLibDirs ) @@ -317,7 +353,8 @@ void cmTarget::Emit( const std::string& lib, void cmTarget::GatherDependencies( const cmMakefile& mf, const std::string& lib, DependencyMap& dep_map, - LibTypeMap& lib_map ) const + LibTypeMap& lib_map, + bool addLibDirs ) { // If the library is already in the dependency map, then it has // already been fully processed. @@ -343,7 +380,20 @@ void cmTarget::GatherDependencies( const cmMakefile& mf, std::string l = depline.substr( start, end-start ); if( l.size() != 0 ) { - const std::string cname = l; + if( addLibDirs ) + { + const char* libpath = mf.GetDefinition( l.c_str() ); + if( libpath ) + { + // Don't add a link directory that is already present. + if(std::find(m_LinkDirectories.begin(), + m_LinkDirectories.end(), libpath) == m_LinkDirectories.end()) + { + m_LinkDirectories.push_back(libpath); + } + } + } + const std::string& cname = l; std::string linkType = l; linkType += "_LINK_TYPE"; cmTarget::LinkLibraryType llt = cmTarget::GENERAL; @@ -361,7 +411,7 @@ void cmTarget::GatherDependencies( const cmMakefile& mf, } lib_map[ cname ] = std::make_pair(l,llt); dep_map[ lib ].insert( cname ); - GatherDependencies( mf, cname, dep_map, lib_map ); + GatherDependencies( mf, cname, dep_map, lib_map, addLibDirs ); } start = end+1; // skip the ; end = depline.find( ";", start ); |