From 8112059ee7f38f0eb5cdcaba8185aec659abcbfc Mon Sep 17 00:00:00 2001 From: Deniz Bahadir Date: Mon, 27 Nov 2017 22:30:26 +0100 Subject: target_link_libraries: Simplify implementation and add comments. The implementation of `target_link_libraries` did grow over the years when new features where added. This commit cleans up the implementation and adds comments to better document its intention. The behavior of `target_link_libraries` itself is left untouched. --- Source/cmTargetLinkLibrariesCommand.cxx | 121 ++++++++++++++++++-------------- 1 file changed, 67 insertions(+), 54 deletions(-) (limited to 'Source/cmTargetLinkLibrariesCommand.cxx') diff --git a/Source/cmTargetLinkLibrariesCommand.cxx b/Source/cmTargetLinkLibrariesCommand.cxx index 65ab544348..97bb0a21cd 100644 --- a/Source/cmTargetLinkLibrariesCommand.cxx +++ b/Source/cmTargetLinkLibrariesCommand.cxx @@ -25,16 +25,17 @@ const char* cmTargetLinkLibrariesCommand::LinkLibraryTypeNames[3] = { bool cmTargetLinkLibrariesCommand::InitialPass( std::vector const& args, cmExecutionStatus&) { - // must have one argument + // Must have at least one argument. if (args.empty()) { this->SetError("called with incorrect number of arguments"); return false; } - + // Alias targets cannot be on the LHS of this command. if (this->Makefile->IsAlias(args[0])) { this->SetError("can not be used on an ALIAS target."); return false; } + // Lookup the target for which libraries are specified. this->Target = this->Makefile->GetCMakeInstance()->GetGlobalGenerator()->FindTarget( @@ -78,8 +79,7 @@ bool cmTargetLinkLibrariesCommand::InitialPass( break; } } - - // now actually print the message + // Now actually print the message. switch (t) { case cmake::AUTHOR_WARNING: this->Makefile->IssueMessage(cmake::AUTHOR_WARNING, e.str()); @@ -94,6 +94,7 @@ bool cmTargetLinkLibrariesCommand::InitialPass( return true; } + // OBJECT libraries are not allowed on the LHS of the command. if (this->Target->GetType() == cmStateEnums::OBJECT_LIBRARY) { std::ostringstream e; e << "Object library target \"" << args[0] << "\" " @@ -103,6 +104,7 @@ bool cmTargetLinkLibrariesCommand::InitialPass( return true; } + // Having a UTILITY library on the LHS is a bug. if (this->Target->GetType() == cmStateEnums::UTILITY) { std::ostringstream e; const char* modal = nullptr; @@ -129,7 +131,7 @@ bool cmTargetLinkLibrariesCommand::InitialPass( } } - // but we might not have any libs after variable expansion + // But we might not have any libs after variable expansion. if (args.size() < 2) { return true; } @@ -142,8 +144,8 @@ bool cmTargetLinkLibrariesCommand::InitialPass( // specification if the keyword is encountered as the first argument. this->CurrentProcessingState = ProcessingLinkLibraries; - // add libraries, note that there is an optional prefix - // of debug and optimized that can be used + // Add libraries, note that there is an optional prefix + // of debug and optimized that can be used. for (unsigned int i = 1; i < args.size(); ++i) { if (args[i] == "LINK_INTERFACE_LIBRARIES") { this->CurrentProcessingState = ProcessingPlainLinkInterface; @@ -366,10 +368,13 @@ bool cmTargetLinkLibrariesCommand::HandleLibrary(const std::string& lib, } } - // Handle normal case first. + // Handle normal case where the command was called with another keyword than + // INTERFACE / LINK_INTERFACE_LIBRARIES or none at all. (The "LINK_LIBRARIES" + // property of the target on the LHS shall be populated.) if (this->CurrentProcessingState != ProcessingKeywordLinkInterface && this->CurrentProcessingState != ProcessingPlainLinkInterface) { + // Assure that the target on the LHS was created in the current directory. cmTarget* t = this->Makefile->FindLocalNonAliasTarget(this->Target->GetName()); if (!t) { @@ -408,72 +413,80 @@ bool cmTargetLinkLibrariesCommand::HandleLibrary(const std::string& lib, } this->Target->AddLinkLibrary(*this->Makefile, lib, llt); + } - if (this->CurrentProcessingState == ProcessingLinkLibraries) { - this->Target->AppendProperty( - "INTERFACE_LINK_LIBRARIES", - this->Target->GetDebugGeneratorExpressions(lib, llt).c_str()); - return true; - } - if (this->CurrentProcessingState != ProcessingKeywordPublicInterface && - this->CurrentProcessingState != ProcessingPlainPublicInterface) { - if (this->Target->GetType() == cmStateEnums::STATIC_LIBRARY) { - std::string configLib = - this->Target->GetDebugGeneratorExpressions(lib, llt); - if (cmGeneratorExpression::IsValidTargetName(lib) || - cmGeneratorExpression::Find(lib) != std::string::npos) { - configLib = "$"; - } - this->Target->AppendProperty("INTERFACE_LINK_LIBRARIES", - configLib.c_str()); + // Handle (additional) case where the command was called with PRIVATE / + // LINK_PRIVATE and stop its processing. (The "INTERFACE_LINK_LIBRARIES" + // property of the target on the LHS shall only be populated if it is a + // STATIC library.) + if (this->CurrentProcessingState == ProcessingKeywordPrivateInterface || + this->CurrentProcessingState == ProcessingPlainPrivateInterface) { + if (this->Target->GetType() == cmStateEnums::STATIC_LIBRARY) { + std::string configLib = + this->Target->GetDebugGeneratorExpressions(lib, llt); + if (cmGeneratorExpression::IsValidTargetName(lib) || + cmGeneratorExpression::Find(lib) != std::string::npos) { + configLib = "$"; } - // Not a 'public' or 'interface' library. Do not add to interface - // property. - return true; + this->Target->AppendProperty("INTERFACE_LINK_LIBRARIES", + configLib.c_str()); } + return true; } + // Handle general case where the command was called with another keyword than + // PRIVATE / LINK_PRIVATE or none at all. (The "INTERFACE_LINK_LIBRARIES" + // property of the target on the LHS shall be populated.) this->Target->AppendProperty( "INTERFACE_LINK_LIBRARIES", this->Target->GetDebugGeneratorExpressions(lib, llt).c_str()); + // Stop processing if called without any keyword. + if (this->CurrentProcessingState == ProcessingLinkLibraries) { + return true; + } + // Stop processing if policy CMP0022 is set to NEW. const cmPolicies::PolicyStatus policy22Status = this->Target->GetPolicyStatusCMP0022(); - if (policy22Status != cmPolicies::OLD && policy22Status != cmPolicies::WARN) { return true; } - + // Stop processing if called with an INTERFACE library on the LHS. if (this->Target->GetType() == cmStateEnums::INTERFACE_LIBRARY) { return true; } - // Get the list of configurations considered to be DEBUG. - std::vector debugConfigs = - this->Makefile->GetCMakeInstance()->GetDebugConfigs(); - std::string prop; - - // Include this library in the link interface for the target. - if (llt == DEBUG_LibraryType || llt == GENERAL_LibraryType) { - // Put in the DEBUG configuration interfaces. - for (std::string const& dc : debugConfigs) { - prop = "LINK_INTERFACE_LIBRARIES_"; - prop += dc; - this->Target->AppendProperty(prop, lib.c_str()); + // Handle (additional) backward-compatibility case where the command was + // called with PUBLIC / INTERFACE / LINK_PUBLIC / LINK_INTERFACE_LIBRARIES. + // (The policy CMP0022 is not set to NEW.) + { + // Get the list of configurations considered to be DEBUG. + std::vector debugConfigs = + this->Makefile->GetCMakeInstance()->GetDebugConfigs(); + std::string prop; + + // Include this library in the link interface for the target. + if (llt == DEBUG_LibraryType || llt == GENERAL_LibraryType) { + // Put in the DEBUG configuration interfaces. + for (std::string const& dc : debugConfigs) { + prop = "LINK_INTERFACE_LIBRARIES_"; + prop += dc; + this->Target->AppendProperty(prop, lib.c_str()); + } } - } - if (llt == OPTIMIZED_LibraryType || llt == GENERAL_LibraryType) { - // Put in the non-DEBUG configuration interfaces. - this->Target->AppendProperty("LINK_INTERFACE_LIBRARIES", lib.c_str()); - - // Make sure the DEBUG configuration interfaces exist so that the - // general one will not be used as a fall-back. - for (std::string const& dc : debugConfigs) { - prop = "LINK_INTERFACE_LIBRARIES_"; - prop += dc; - if (!this->Target->GetProperty(prop)) { - this->Target->SetProperty(prop, ""); + if (llt == OPTIMIZED_LibraryType || llt == GENERAL_LibraryType) { + // Put in the non-DEBUG configuration interfaces. + this->Target->AppendProperty("LINK_INTERFACE_LIBRARIES", lib.c_str()); + + // Make sure the DEBUG configuration interfaces exist so that the + // general one will not be used as a fall-back. + for (std::string const& dc : debugConfigs) { + prop = "LINK_INTERFACE_LIBRARIES_"; + prop += dc; + if (!this->Target->GetProperty(prop)) { + this->Target->SetProperty(prop, ""); + } } } } -- cgit v1.2.1