BUG: the dependency analysis would incorrectly alphabetically re-order the

link lines, which affects external libraries pulled up from deep within
the dependency tree. Fixed by preserving order everywhere.
This commit is contained in:
Amitha Perera 2002-11-19 18:01:05 -05:00
parent 7140c6f364
commit 939035ad91
17 changed files with 357 additions and 129 deletions

View File

@ -262,6 +262,20 @@ IF(BUILD_TESTING)
Exec
${CMake_BINARY_DIR}/Tests/LinkLine
LinkLine)
ADD_TEST(linkorder1 ${CMake_BINARY_DIR}/Source/cmaketest
${CMake_SOURCE_DIR}/Tests/LinkLineOrder
${CMake_BINARY_DIR}/Tests/LinkLineOrder
Exec1
${CMake_BINARY_DIR}/Tests/LinkLineOrder
LinkLineOrder)
ADD_TEST(linkorder2 ${CMake_BINARY_DIR}/Source/cmaketest
${CMake_SOURCE_DIR}/Tests/LinkLineOrder
${CMake_BINARY_DIR}/Tests/LinkLineOrder
Exec2
${CMake_BINARY_DIR}/Tests/LinkLineOrder
LinkLineOrder)
ENDIF(BUILD_TESTING)

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@ -636,15 +636,11 @@ void cmMakefile::AddLibrary(const char* lname, int shared,
default:
target.SetType(cmTarget::STATIC_LIBRARY);
}
// Clear its dependencies. Otherwise, dependencies might persist
// over changes in CMakeLists.txt, making the information stale and
// hence useless.
std::string depname = lname;
depname += "_LIB_DEPENDS";
this->GetCacheManager()->
AddCacheEntry(depname.c_str(), "",
"Dependencies for target", cmCacheManager::STATIC);
target.ClearDependencyInformation( *this, lname );
target.SetInAll(true);
target.GetSourceLists() = srcs;
@ -690,7 +686,6 @@ void cmMakefile::AddLibrary(const char* lname, int shared,
"Whether a library is static, shared or module.",
cmCacheManager::INTERNAL);
}
}
void cmMakefile::AddExecutable(const char *exeName,

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@ -22,6 +22,18 @@
#include <set>
void cmTarget::SetType(TargetType type)
{
// only add dependency information for library targets
m_TargetType = type;
if(m_TargetType >= STATIC_LIBRARY && m_TargetType <= MODULE_LIBRARY) {
m_RecordDependencies = true;
} else {
m_RecordDependencies = false;
}
}
void cmTarget::GenerateSourceFilesFromSourceLists( cmMakefile &mf)
{
// this is only done for non install targets
@ -136,6 +148,33 @@ void cmTarget::AddLinkDirectory(const char* d)
}
void cmTarget::ClearDependencyInformation( cmMakefile& mf, const char* target )
{
// Clear the dependencies. The cache variable must exist iff we are
// recording dependency information for this target.
std::string depname = target;
depname += "_LIB_DEPENDS";
if (m_RecordDependencies)
{
mf.AddCacheDefinition(depname.c_str(), "",
"Dependencies for target", cmCacheManager::STATIC);
}
else
{
if (mf.GetDefinition( depname.c_str() ))
{
std::string message = "Target ";
message += target;
message += " has dependency information when it shouldn't.\n";
message += "Your cache is probably stale. Please remove the entry\n ";
message += depname;
message += "\nfrom the cache.";
cmSystemTools::Error( message.c_str() );
}
}
}
void cmTarget::AddLinkLibrary(const std::string& lib,
LinkLibraryType llt)
@ -178,8 +217,11 @@ void cmTarget::AddLinkLibrary(cmMakefile& mf,
// simply a set of libraries separated by ";". There should always
// be a trailing ";". These library names are not canonical, in that
// they may be "-framework x", "-ly", "/path/libz.a", etc.
// only add depend information for library targets
if(m_TargetType >= STATIC_LIBRARY && m_TargetType <= MODULE_LIBRARY)
// We shouldn't remove duplicates here because external libraries
// may be purposefully duplicated to handle recursive dependencies,
// and we removing one instance will break the link line. Duplicates
// will be appropriately eliminated at emit time.
if(m_RecordDependencies)
{
std::string targetEntry = target;
targetEntry += "_LIB_DEPENDS";
@ -189,11 +231,8 @@ void cmTarget::AddLinkLibrary(cmMakefile& mf,
{
dependencies += old_val;
}
if( dependencies.find( lib ) == std::string::npos )
{
dependencies += lib;
dependencies += ";";
}
dependencies += lib;
dependencies += ";";
mf.AddCacheDefinition( targetEntry.c_str(), dependencies.c_str(),
"Dependencies for the target",
cmCacheManager::STATIC );
@ -250,44 +289,82 @@ cmTarget::AnalyzeLibDependencies( const cmMakefile& mf )
//
// Also, we will leave the original link line intact; we will just add any
// dependencies that were missing.
//
// There is a problem with recursive external libraries
// (i.e. libraries with no dependency information that are
// recursively dependent). We must make sure that the we emit one of
// the libraries twice to satisfy the recursion, but we shouldn't
// emit it more times than necessary. In particular, we must make
// sure that handling this improbable case doesn't cost us when
// dealing with the common case of non-recursive libraries. The
// solution is to assume that the recursion is satisfied at one node
// of the dependency tree. To illustrate, assume libA and libB are
// extrenal and mutually dependent. Suppose libX depends on
// libA, and libY on libA and libX. Then
// TARGET_LINK_LIBRARIES( Y X A B A )
// TARGET_LINK_LIBRARIES( X A B A )
// TARGET_LINK_LIBRARIES( Exec Y )
// would result in "-lY -lX -lA -lB -lA". This is the correct way to
// specify the dependencies, since the mutual dependency of A and B
// is resolved *every time libA is specified*.
//
// Something like
// TARGET_LINK_LIBRARIES( Y X A B A )
// TARGET_LINK_LIBRARIES( X A B )
// TARGET_LINK_LIBRARIES( Exec Y )
// would result in "-lY -lX -lA -lB", and the mutual dependency
// information is lost. This is because in some case (Y), the mutual
// dependency of A and B is listed, while in another other case (X),
// it is not. Depending on which line actually emits A, the mutual
// dependency may or may not be on the final link line. We can't
// handle this pathalogical case cleanly without emitting extra
// libraries for the normal cases. Besides, the dependency
// information for X is wrong anyway: if we build an executable
// depending on X alone, we would not have the mutual dependency on
// A and B resolved.
//
// IMPROVEMENTS:
// -- The current algorithm will not always pick the "optimal" link line
// when recursive dependencies are present. It will instead break the
// cycles at an aribtrary point. The majority of projects won't have
// cyclic dependencies, so this is probably not a big deal. Note that
// the link line is always correct, just not necessary optimal.
typedef std::vector< std::string > LinkLine;
// The dependency map.
DependencyMap dep_map;
// Keeps track of which dependencies have already been emitted for a given
// target. This could be via this function, or because they were already
// satisfied on the original link line.
DependencyMap satisfied;
// 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);
// 1. Determine the dependencies already satisfied by the original link
// line.
// 1. Build the dependency graph
//
for(LinkLibraries::reverse_iterator lib = m_LinkLibraries.rbegin();
lib != m_LinkLibraries.rend(); ++lib)
{
this->GatherDependencies( mf, lib->first, dep_map );
}
// 2. Remove any dependencies that are already satisfied in the original
// link line.
//
for(LinkLibraries::iterator lib = m_LinkLibraries.begin();
lib != m_LinkLibraries.end(); ++lib)
{
for( LinkLibraries::iterator lib2 = lib;
lib2 != m_LinkLibraries.end(); ++lib2)
{
satisfied[ lib->first ].insert( lib2->first );
DeleteDependency( dep_map, lib->first, lib2->first );
}
}
// 2. Build the explicit dependency map
for(LinkLibraries::reverse_iterator lib = m_LinkLibraries.rbegin();
lib != m_LinkLibraries.rend(); ++lib)
{
this->GatherDependencies( mf, lib->first, dep_map );
}
// 3. Create the new link line by simply emitting any dependencies that are
// missing. Start from the back and keep adding.
//
std::set<cmStdString> done, visited;
std::vector<std::string> newLinkLibraries;
for(LinkLibraries::reverse_iterator lib = m_LinkLibraries.rbegin();
@ -295,26 +372,15 @@ cmTarget::AnalyzeLibDependencies( const cmMakefile& mf )
{
// skip zero size library entries, this may happen
// if a variable expands to nothing.
if (lib->first.size() == 0) continue;
// Emit all the dependencies that are not already satisfied on the
// original link line.
if( dep_map.find(lib->first) != dep_map.end() ) // does it have dependencies?
if (lib->first.size() != 0)
{
const std::set<cmStdString>& dep_on = dep_map.find( lib->first )->second;
std::set<cmStdString>::const_iterator i;
for( i = dep_on.begin(); i != dep_on.end(); ++i )
{
if( satisfied[lib->first].end() == satisfied[lib->first].find( *i ) )
{
Emit( *i, dep_map, done, visited, newLinkLibraries );
}
}
Emit( lib->first, dep_map, done, visited, newLinkLibraries );
}
}
// 4. Add the new libraries to the link line.
// 4. Add the new libraries to the link line.
//
for( std::vector<std::string>::reverse_iterator k = newLinkLibraries.rbegin();
k != newLinkLibraries.rend(); ++k )
{
@ -322,6 +388,8 @@ cmTarget::AnalyzeLibDependencies( const cmMakefile& mf )
{
// who the hell knows what this is, I think that K contains the
// name of a library but ... Ken
// k contains the same stuff that are on the LINK_LIBRARIES
// commands. Normally, they would just be library names. -- Amitha.
std::string libPathStr = *k + "_CMAKE_PATH";
const char* libpath = mf.GetDefinition( libPathStr.c_str() );
if( libpath )
@ -354,7 +422,31 @@ cmTarget::AnalyzeLibDependencies( const cmMakefile& mf )
}
void cmTarget::InsertDependency( DependencyMap& depMap,
const cmStdString& lib,
const cmStdString& dep ) const
{
depMap[lib].push_back(dep);
}
void cmTarget::DeleteDependency( DependencyMap& depMap,
const cmStdString& lib,
const cmStdString& dep ) const
{
// Make sure there is an entry in the map for lib. If so, delete all
// dependencies to dep. There may be repeated entries because of
// external libraries that are specified multiple times.
DependencyMap::iterator map_itr = depMap.find( lib );
if( map_itr != depMap.end() )
{
DependencyList& depList = map_itr->second;
DependencyList::iterator itr;
while( (itr = std::find(depList.begin(), depList.end(), dep)) != depList.end() )
{
depList.erase( itr );
}
}
}
void cmTarget::Emit( const std::string& lib,
const DependencyMap& dep_map,
@ -364,30 +456,56 @@ void cmTarget::Emit( const std::string& lib,
{
// It's already been emitted
if( emitted.find(lib) != emitted.end() )
{
return;
}
// If this library hasn't been visited before, then emit all its
// dependencies before emitting the library itself. If it has been
// visited before, then there is a dependency cycle. Just emit the
// library itself, and let the recursion that got us here deal with
// emitting the dependencies for the library.
// Emit the dependencies only if this library node hasn't been
// visited before. If it has, then we have a cycle. The recursion
// that got us here should take care of everything.
if( visited.insert(lib).second )
{
if( dep_map.find(lib) != dep_map.end() ) // does it have dependencies?
{
const std::set<cmStdString>& dep_on = dep_map.find( lib )->second;
std::set<cmStdString>::const_iterator i;
for( i = dep_on.begin(); i != dep_on.end(); ++i )
const DependencyList& dep_on = dep_map.find( lib )->second;
DependencyList::const_reverse_iterator i;
// To cater for recursive external libraries, we must emit
// duplicates on this link line *unless* they were emitted by
// some other node, in which case we assume that the recursion
// was resolved then. We making the simplifying assumption that
// any duplicates on a single link line are on purpose, and must
// be preserved.
// This variable will keep track of the libraries that were
// emitted directory from the current node, and not from a
// recursive call. This way, if we come across a library that
// has already been emitted, we repeat it iff it has been
// emitted here.
std::set<cmStdString> emitted_here;
for( i = dep_on.rbegin(); i != dep_on.rend(); ++i )
{
Emit( *i, dep_map, emitted, visited, link_line );
if( emitted_here.find(*i) != emitted_here.end() )
{
// a repeat. Must emit.
emitted.insert(*i);
link_line.push_back( *i );
}
else
{
// Emit only if no-one else has
if( emitted.find(*i) == emitted.end() )
{
// emit dependencies
Emit( *i, dep_map, emitted, visited, link_line );
// emit self
emitted.insert(*i);
emitted_here.insert(*i);
link_line.push_back( *i );
}
}
}
}
}
link_line.push_back( lib );
emitted.insert(lib);
}
@ -419,55 +537,12 @@ void cmTarget::GatherDependencies( const cmMakefile& mf,
std::string l = depline.substr( start, end-start );
if( l.size() != 0 )
{
dep_map[ lib ].insert( l );
InsertDependency( dep_map, lib, l );
GatherDependencies( mf, l, dep_map );
}
start = end+1; // skip the ;
end = depline.find( ";", start );
}
dep_map[lib].erase(lib); // cannot depend on itself
DeleteDependency( dep_map, lib, lib); // cannot depend on itself
}
}
// return true if lib1 depends on lib2
bool cmTarget::DependsOn( const std::string& lib1, const std::string& lib2,
const DependencyMap& dep_map,
std::set<cmStdString>& visited ) const
{
if( !visited.insert( lib1 ).second )
{
return false; // already visited here
}
if( lib1 == lib2 )
{
return false;
}
if( dep_map.find(lib1) == dep_map.end() )
{
return false; // lib1 doesn't have any dependencies
}
const std::set<cmStdString>& dep_set = dep_map.find(lib1)->second;
if( dep_set.end() != dep_set.find( lib2 ) )
{
return true; // lib1 doesn't directly depend on lib2.
}
// Do a recursive check: does lib1 depend on x which depends on lib2?
for( std::set<cmStdString>::const_iterator itr = dep_set.begin();
itr != dep_set.end(); ++itr )
{
if( this->DependsOn( *itr, lib2, dep_map, visited ) )
{
return true;
}
}
return false;
}

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@ -42,8 +42,11 @@ public:
return m_TargetType;
}
void SetType(TargetType f) { m_TargetType = f; }
/**
* Set the target type
*/
void SetType(TargetType f);
/**
* Indicate whether the target is part of the all target
*/
@ -80,6 +83,11 @@ public:
typedef std::vector<std::pair<std::string,LinkLibraryType> > LinkLibraries;
const LinkLibraries &GetLinkLibraries() const {return m_LinkLibraries;}
/**
* Clear the dependency information recorded for this target, if any.
*/
void ClearDependencyInformation(cmMakefile& mf, const char* target);
void AddLinkLibrary(cmMakefile& mf,
const char *target, const char* lib,
LinkLibraryType llt);
@ -119,10 +127,17 @@ public:
private:
/**
* This map holds the dependency graph. map[x] returns a set of
* direct dependencies of x.
* A list of direct dependencies. Use in conjunction with DependencyMap.
*/
typedef std::map< cmStdString, std::set< cmStdString > > DependencyMap;
typedef std::vector<cmStdString> DependencyList;
/**
* This map holds the dependency graph. map[x] returns a set of
* direct dependencies of x. Note that the direct depenencies are
* ordered. This is necessary to handle direct dependencies that
* themselves have no dependency information.
*/
typedef std::map< cmStdString, std::vector< cmStdString > > DependencyMap;
/**
* Maps a library name to its internal structure
@ -130,12 +145,26 @@ private:
typedef std::map< cmStdString, std::pair<cmStdString,LinkLibraryType> > LibTypeMap;
/**
* Emits the library \param lib and all its dependencies into
* link_line. \param emitted keeps track of the libraries that have
* been emitted to avoid duplicates--it is more efficient than
* searching link_line. \param visited is used detect cycles. Note
* that \param link_line is in reverse order, in that the
* dependencies of a library are listed before the library itself.
* Inserts \a dep at the end of the dependency list of \a lib.
*/
void InsertDependency( DependencyMap& depMap,
const cmStdString& lib,
const cmStdString& dep ) const;
/*
* Deletes \a dep from the dependency list of \a lib.
*/
void DeleteDependency( DependencyMap& depMap,
const cmStdString& lib,
const cmStdString& dep ) const;
/**
* Emits the library \a lib and all its dependencies into link_line.
* \a emitted keeps track of the libraries that have been emitted to
* avoid duplicates--it is more efficient than searching
* link_line. \a visited is used detect cycles. Note that \a
* link_line is in reverse order, in that the dependencies of a
* library are listed before the library itself.
*/
void Emit( const std::string& lib,
const DependencyMap& dep_map,
@ -144,25 +173,12 @@ private:
std::vector<std::string>& link_line ) const;
/**
* Finds the explicit dependencies for \param lib, if they have been
* specified, and inserts them into \param dep_map. It also adds the
* maps from the library names to internal structures for any
* libraries introduced by the analysis. \param addLibDirs is true
* if paths to newly found libraries should be added to the search
* path.
* Finds the dependencies for \a lib and inserts them into \a
* dep_map.
*/
void GatherDependencies( const cmMakefile& mf, const std::string& lib,
DependencyMap& dep_map );
/**
* Returns true if lib1 depends on lib2 according to \param
* dep_map. \param visited is used to prevent infinite loops when
* cycles are present.
*/
bool DependsOn( const std::string& lib1, const std::string& lib2,
const DependencyMap& dep_map,
std::set<cmStdString>& visited ) const;
private:
std::vector<cmCustomCommand> m_CustomCommands;
std::vector<std::string> m_SourceLists;
@ -174,6 +190,7 @@ private:
bool m_InAll;
std::string m_InstallPath;
std::set<cmStdString> m_Utilities;
bool m_RecordDependencies;
};
typedef std::map<cmStdString,cmTarget> cmTargets;

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@ -0,0 +1,36 @@
PROJECT( LinkLineOrder )
# This tests ensures that the order of libraries are preserved when
# they don't have dependency information, even if they are deep in the
# dependency tree.
# NoDepC depends on NoDepA which depends on NoDepB. NoDepE and NoDepF
# are dependent on each other (recursive dependency). However, CMake
# has no information about these libraries except for the order they
# are specified in One. We must make sure we don't lose that.
ADD_LIBRARY( NoDepA NoDepA.c )
ADD_LIBRARY( NoDepB NoDepB.c )
ADD_LIBRARY( NoDepC NoDepC.c )
ADD_LIBRARY( NoDepE NoDepE.c )
ADD_LIBRARY( NoDepF NoDepF.c )
ADD_LIBRARY( One One.c )
TARGET_LINK_LIBRARIES( One NoDepC NoDepA NoDepB NoDepE NoDepF NoDepE )
ADD_EXECUTABLE( Exec1 Exec1.c )
TARGET_LINK_LIBRARIES( Exec1 One )
# Similar situation as One, except at a different level of the
# dependency tree. This makes sure that the order is presevered
# everywhere in the graph.
ADD_LIBRARY( NoDepX NoDepX.c )
ADD_LIBRARY( NoDepY NoDepY.c )
ADD_LIBRARY( NoDepZ NoDepZ.c )
ADD_LIBRARY( Two Two.c )
TARGET_LINK_LIBRARIES( Two One NoDepZ NoDepX NoDepY )
ADD_EXECUTABLE( Exec2 Exec2.c )
TARGET_LINK_LIBRARIES( Exec2 Two )

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@ -0,0 +1,8 @@
// Directly depends on One
void OneFunc();
int main()
{
OneFunc();
return 0;
}

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@ -0,0 +1,8 @@
// Directly depends on Two
void TwoFunc();
int main()
{
TwoFunc();
return 0;
}

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@ -0,0 +1,7 @@
// depends on NoDepB
void NoDepB_func();
void NoDepA_func()
{
NoDepB_func();
}

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@ -0,0 +1,4 @@
// No dependencies
void NoDepB_func()
{
}

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@ -0,0 +1,7 @@
// depends on NoDepA
void NoDepA_func();
void NoDepC_func()
{
NoDepA_func();
}

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@ -0,0 +1,11 @@
// depends on NoDepF
void NoDepF_func();
void NoDepE_func()
{
static int firstcall = 1;
if( firstcall ) {
firstcall = 0;
NoDepF_func();
}
}

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@ -0,0 +1,11 @@
// depends on NoDepE
void NoDepE_func();
void NoDepF_func()
{
static int firstcall = 1;
if( firstcall ) {
firstcall = 0;
NoDepE_func();
}
}

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@ -0,0 +1,7 @@
// depends on NoDepY
void NoDepY_func();
void NoDepX_func()
{
NoDepY_func();
}

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@ -0,0 +1,4 @@
// No dependencies
void NoDepY_func()
{
}

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@ -0,0 +1,7 @@
// depends on NoDepX
void NoDepX_func();
void NoDepZ_func()
{
NoDepX_func();
}

10
Tests/LinkLineOrder/One.c Normal file
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@ -0,0 +1,10 @@
// depends on NoDepC and NoDepE (and hence on NoDepA, NoDepB and
// NoDepF)
void NoDepC_func();
void NoDepE_func();
void OneFunc()
{
NoDepC_func();
NoDepE_func();
}

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@ -0,0 +1,7 @@
void OneFunc();
void TwoFunc()
{
OneFunc();
NoDepZ_func();
}