From 711b63f7e095992d6ab84063af076d23a916b1f3 Mon Sep 17 00:00:00 2001 From: Brad King Date: Thu, 6 Dec 2012 09:59:18 -0500 Subject: Add policy CMP0019 to skip include/link variable re-expansion Historically CMake has always expanded ${} variable references in the values given to include_directories(), link_directories(), and link_libraries(). This has been unnecessary since general ${} evaluation syntax was added to the language a LONG time ago, but has remained for compatibility with VERY early CMake versions. For a long time the re-expansion was a lightweight operation because it was only processed once at the directory level and the fast-path of cmMakefile::ExpandVariablesInString was usually taken because values did not have any '$' in them. Then commit d899eb71 (Call ExpandVariablesInString for each target's INCLUDE_DIRECTORIES, 2012-02-22) made the operation a bit heavier because the expansion is now needed on a per-target basis. In the future we will support generator expressions in INCLUDE_DIRECTORIES with $<> syntax, so the fast-path in cmMakefile::ExpandVariablesInString will no longer be taken and re-expansion will be very expensive. Add policy CMP0019 to skip the re-expansion altogether in NEW behavior. In OLD behavior perform the expansion but improve the fast-path heuristic to match ${} but not $<>. If the policy is not set then warn if expansion actually does anything. We expect this to be encountered very rarely in practice. --- Source/cmMakefile.cxx | 75 +++++++++++++++++++++----- Source/cmMakefile.h | 2 +- Source/cmPolicies.cxx | 17 ++++++ Source/cmPolicies.h | 1 + Tests/RunCMake/CMP0019/CMP0019-NEW.cmake | 2 + Tests/RunCMake/CMP0019/CMP0019-OLD.cmake | 2 + Tests/RunCMake/CMP0019/CMP0019-WARN-stderr.txt | 40 ++++++++++++++ Tests/RunCMake/CMP0019/CMP0019-WARN.cmake | 1 + Tests/RunCMake/CMP0019/CMP0019-code.cmake | 9 ++++ Tests/RunCMake/CMP0019/CMakeLists.txt | 3 ++ Tests/RunCMake/CMP0019/RunCMakeTest.cmake | 5 ++ Tests/RunCMake/CMakeLists.txt | 1 + 12 files changed, 145 insertions(+), 13 deletions(-) create mode 100644 Tests/RunCMake/CMP0019/CMP0019-NEW.cmake create mode 100644 Tests/RunCMake/CMP0019/CMP0019-OLD.cmake create mode 100644 Tests/RunCMake/CMP0019/CMP0019-WARN-stderr.txt create mode 100644 Tests/RunCMake/CMP0019/CMP0019-WARN.cmake create mode 100644 Tests/RunCMake/CMP0019/CMP0019-code.cmake create mode 100644 Tests/RunCMake/CMP0019/CMakeLists.txt create mode 100644 Tests/RunCMake/CMP0019/RunCMakeTest.cmake diff --git a/Source/cmMakefile.cxx b/Source/cmMakefile.cxx index 8498d72..d943c45 100644 --- a/Source/cmMakefile.cxx +++ b/Source/cmMakefile.cxx @@ -814,7 +814,7 @@ bool cmMakefile::NeedBackwardsCompatibility(unsigned int major, void cmMakefile::FinalPass() { // do all the variable expansions here - this->ExpandVariables(); + this->ExpandVariablesCMP0019(); // give all the commands a chance to do something // after the file has been parsed before generation @@ -2122,21 +2122,33 @@ void cmMakefile::AddExtraDirectory(const char* dir) this->AuxSourceDirectories.push_back(dir); } +static bool mightExpandVariablesCMP0019(const char* s) +{ + return s && *s && strstr(s,"${") && strchr(s,'}'); +} -// expand CMAKE_BINARY_DIR and CMAKE_SOURCE_DIR in the -// include and library directories. - -void cmMakefile::ExpandVariables() +void cmMakefile::ExpandVariablesCMP0019() { - // Now expand variables in the include and link strings + // Drop this ancient compatibility behavior with a policy. + cmPolicies::PolicyStatus pol = this->GetPolicyStatus(cmPolicies::CMP0019); + if(pol != cmPolicies::OLD && pol != cmPolicies::WARN) + { + return; + } + cmOStringStream w; - // May not be necessary anymore... But may need a policy for strict - // backwards compatibility const char *includeDirs = this->GetProperty("INCLUDE_DIRECTORIES"); - if (includeDirs) + if(mightExpandVariablesCMP0019(includeDirs)) { std::string dirs = includeDirs; this->ExpandVariablesInString(dirs, true, true); + if(pol == cmPolicies::WARN && dirs != includeDirs) + { + w << "Evaluated directory INCLUDE_DIRECTORIES\n" + << " " << includeDirs << "\n" + << "as\n" + << " " << dirs << "\n"; + } this->SetProperty("INCLUDE_DIRECTORIES", dirs.c_str()); } @@ -2146,10 +2158,17 @@ void cmMakefile::ExpandVariables() { cmTarget &t = l->second; includeDirs = t.GetProperty("INCLUDE_DIRECTORIES"); - if (includeDirs) + if(mightExpandVariablesCMP0019(includeDirs)) { std::string dirs = includeDirs; this->ExpandVariablesInString(dirs, true, true); + if(pol == cmPolicies::WARN && dirs != includeDirs) + { + w << "Evaluated target " << t.GetName() << " INCLUDE_DIRECTORIES\n" + << " " << includeDirs << "\n" + << "as\n" + << " " << dirs << "\n"; + } t.SetProperty("INCLUDE_DIRECTORIES", dirs.c_str()); } } @@ -2157,13 +2176,45 @@ void cmMakefile::ExpandVariables() for(std::vector::iterator d = this->LinkDirectories.begin(); d != this->LinkDirectories.end(); ++d) { - this->ExpandVariablesInString(*d, true, true); + if(mightExpandVariablesCMP0019(d->c_str())) + { + std::string orig = *d; + this->ExpandVariablesInString(*d, true, true); + if(pol == cmPolicies::WARN && *d != orig) + { + w << "Evaluated link directory\n" + << " " << orig << "\n" + << "as\n" + << " " << *d << "\n"; + } + } } for(cmTarget::LinkLibraryVectorType::iterator l = this->LinkLibraries.begin(); l != this->LinkLibraries.end(); ++l) { - this->ExpandVariablesInString(l->first, true, true); + if(mightExpandVariablesCMP0019(l->first.c_str())) + { + std::string orig = l->first; + this->ExpandVariablesInString(l->first, true, true); + if(pol == cmPolicies::WARN && l->first != orig) + { + w << "Evaluated link library\n" + << " " << orig << "\n" + << "as\n" + << " " << l->first << "\n"; + } + } + } + + if(!w.str().empty()) + { + cmOStringStream m; + m << this->GetPolicies()->GetPolicyWarning(cmPolicies::CMP0019) + << "\n" + << "The following variable evaluations were encountered:\n" + << w.str(); + this->IssueMessage(cmake::AUTHOR_WARNING, m.str()); } } diff --git a/Source/cmMakefile.h b/Source/cmMakefile.h index 70cfe54..eff05d0 100644 --- a/Source/cmMakefile.h +++ b/Source/cmMakefile.h @@ -693,7 +693,7 @@ public: /** * Expand variables in the makefiles ivars such as link directories etc */ - void ExpandVariables(); + void ExpandVariablesCMP0019(); /** * Replace variables and #cmakedefine lines in the given string. diff --git a/Source/cmPolicies.cxx b/Source/cmPolicies.cxx index 6aef502..eb7d666 100644 --- a/Source/cmPolicies.cxx +++ b/Source/cmPolicies.cxx @@ -491,6 +491,23 @@ cmPolicies::cmPolicies() "CMAKE_SHARED_LIBRARY__FLAGS whether it is modified or not and " "honor the POSITION_INDEPENDENT_CODE target property.", 2,8,9,0, cmPolicies::WARN); + + this->DefinePolicy( + CMP0019, "CMP0019", + "Do not re-expand variables in include and link information.", + "CMake 2.8.10 and lower re-evaluated values given to the " + "include_directories, link_directories, and link_libraries " + "commands to expand any leftover variable references at the " + "end of the configuration step. " + "This was for strict compatibility with VERY early CMake versions " + "because all variable references are now normally evaluated during " + "CMake language processing. " + "CMake 2.8.11 and higher prefer to skip the extra evaluation." + "\n" + "The OLD behavior for this policy is to re-evaluate the values " + "for strict compatibility. " + "The NEW behavior for this policy is to leave the values untouched.", + 2,8,11,0, cmPolicies::WARN); } cmPolicies::~cmPolicies() diff --git a/Source/cmPolicies.h b/Source/cmPolicies.h index 6932565..d7d945c 100644 --- a/Source/cmPolicies.h +++ b/Source/cmPolicies.h @@ -68,6 +68,7 @@ public: CMP0018, ///< Ignore language flags for shared libs, and adhere to /// POSITION_INDEPENDENT_CODE property and *_COMPILE_OPTIONS_PI{E,C} /// instead. + CMP0019, ///< No variable re-expansion in include and link info /** \brief Always the last entry. * diff --git a/Tests/RunCMake/CMP0019/CMP0019-NEW.cmake b/Tests/RunCMake/CMP0019/CMP0019-NEW.cmake new file mode 100644 index 0000000..3091e66 --- /dev/null +++ b/Tests/RunCMake/CMP0019/CMP0019-NEW.cmake @@ -0,0 +1,2 @@ +cmake_policy(SET CMP0019 NEW) +include(CMP0019-code.cmake) diff --git a/Tests/RunCMake/CMP0019/CMP0019-OLD.cmake b/Tests/RunCMake/CMP0019/CMP0019-OLD.cmake new file mode 100644 index 0000000..0f02f9c --- /dev/null +++ b/Tests/RunCMake/CMP0019/CMP0019-OLD.cmake @@ -0,0 +1,2 @@ +cmake_policy(SET CMP0019 OLD) +include(CMP0019-code.cmake) diff --git a/Tests/RunCMake/CMP0019/CMP0019-WARN-stderr.txt b/Tests/RunCMake/CMP0019/CMP0019-WARN-stderr.txt new file mode 100644 index 0000000..03faef9 --- /dev/null +++ b/Tests/RunCMake/CMP0019/CMP0019-WARN-stderr.txt @@ -0,0 +1,40 @@ +CMake Warning \(dev\) in CMakeLists.txt: + Policy CMP0019 is not set: Do not re-expand variables in include and link + information. Run "cmake --help-policy CMP0019" for policy details. Use + the cmake_policy command to set the policy and suppress this warning. + + The following variable evaluations were encountered: + + Evaluated directory INCLUDE_DIRECTORIES + + /usr/include/\${VAR_INCLUDE};/usr/include/normal + + as + + /usr/include/VAL_INCLUDE;/usr/include/normal + + Evaluated target some_target INCLUDE_DIRECTORIES + + /usr/include/\${VAR_INCLUDE};/usr/include/normal + + as + + /usr/include/VAL_INCLUDE;/usr/include/normal + + Evaluated link directory + + /usr/lib/\${VAR_LINK_DIRS} + + as + + /usr/lib/VAL_LINK_DIRS + + Evaluated link library + + \${VAR_LINK_LIBS} + + as + + VAL_LINK_LIBS + +This warning is for project developers. Use -Wno-dev to suppress it.$ diff --git a/Tests/RunCMake/CMP0019/CMP0019-WARN.cmake b/Tests/RunCMake/CMP0019/CMP0019-WARN.cmake new file mode 100644 index 0000000..a419f30 --- /dev/null +++ b/Tests/RunCMake/CMP0019/CMP0019-WARN.cmake @@ -0,0 +1 @@ +include(CMP0019-code.cmake) diff --git a/Tests/RunCMake/CMP0019/CMP0019-code.cmake b/Tests/RunCMake/CMP0019/CMP0019-code.cmake new file mode 100644 index 0000000..26c0e5b --- /dev/null +++ b/Tests/RunCMake/CMP0019/CMP0019-code.cmake @@ -0,0 +1,9 @@ +set(VAR_INCLUDE "VAL_INCLUDE") +set(VAR_LINK_DIRS "VAL_LINK_DIRS") +set(VAR_LINK_LIBS "VAL_LINK_LIBS") +add_custom_target(some_target) +include_directories("/usr/include/\${VAR_INCLUDE}" /usr/include/normal) +link_directories("/usr/lib/\${VAR_LINK_DIRS}" /usr/lib/normal) +link_libraries("\${VAR_LINK_LIBS}" normal) +add_custom_target(other_target) +set_property(TARGET other_target PROPERTY INCLUDE_DIRECTORIES "") diff --git a/Tests/RunCMake/CMP0019/CMakeLists.txt b/Tests/RunCMake/CMP0019/CMakeLists.txt new file mode 100644 index 0000000..e8db6b0 --- /dev/null +++ b/Tests/RunCMake/CMP0019/CMakeLists.txt @@ -0,0 +1,3 @@ +cmake_minimum_required(VERSION 2.8) +project(${RunCMake_TEST} NONE) +include(${RunCMake_TEST}.cmake) diff --git a/Tests/RunCMake/CMP0019/RunCMakeTest.cmake b/Tests/RunCMake/CMP0019/RunCMakeTest.cmake new file mode 100644 index 0000000..119fc2b --- /dev/null +++ b/Tests/RunCMake/CMP0019/RunCMakeTest.cmake @@ -0,0 +1,5 @@ +include(RunCMake) + +run_cmake(CMP0019-WARN) +run_cmake(CMP0019-OLD) +run_cmake(CMP0019-NEW) diff --git a/Tests/RunCMake/CMakeLists.txt b/Tests/RunCMake/CMakeLists.txt index 722d9c3..cc544a3 100644 --- a/Tests/RunCMake/CMakeLists.txt +++ b/Tests/RunCMake/CMakeLists.txt @@ -45,6 +45,7 @@ macro(add_RunCMake_test test) ) endmacro() +add_RunCMake_test(CMP0019) add_RunCMake_test(GeneratorExpression) add_RunCMake_test(TargetPropertyGeneratorExpressions) add_RunCMake_test(Languages) -- cgit v0.12