(0039713)
Anthony Ette (reporter)
2015-10-31 14:54

Specific example:

PROJECT(ec_interface)

# static arhive #1
FILE(TO_CMAKE_PATH $ENV{LIB_INCL_DIR} LIB_INCL)
FIND_LIBRARY(libshm NAMES shm PATHS ${LIB_D} NO_DEFAULT_PATH)
MESSAGE("libshm: " ${libshm})

# static archive 0000002
FILE(TO_CMAKE_PATH /usr/lib USR_LIB)
FIND_LIBRARY(libccur_fbsched NAMES libccur_fbsched.a PATHS ${USR_LIB} NO_DEFAULT_PATH)
MESSAGE("libccur_fbsched: " ${libccur_fbsched})

SET(SOURCES ec_interface.cpp)

TARGET_LINK_LIBRARIES(ec_interface ${libshm} ${libccur_fbsched})

Notice in the resulting linker command below how libshm and libccur_fbsched are handled very differently, why is this?:

/usr/bin/g++ -O3 -DNDEBUG CMakeFiles/ec_interface.dir/ec_interface_w.cpp.o CMakeFiles/ec_interface.dir/ec_interface.cpp.o CMakeFiles/ec_interface.dir/resolver.c.o -o ../../../../ec_interface -rdynamic /sim/lib/v67/ihawk/libshm.a -Wl,-Bstatic -lccur_fbsched -Wl,-Bdynamic

(0039714)
Anthony Ette (reporter)
2015-10-31 14:58

I guess it's also important to note that in LIB_D, only .a files exist (i.e. there is only a libshm.a and no libshm.so file). However, in /usr/lib, there are multiple files by the same name with differenet suffixes (e.g. libccur_fbsched.a, libccur_fbsched.so, etc.). That is why I am specifying the ".a" explicitly in the FIND_LIBRARY command for libccur_fbsched in an attempt to force it to pick up the static archive and not the dynamic ones. The message I'm printing seems to indicate it is using the static, so I still don't understand the resulting link command. How fine tuned of control do I have over the resulting link command? I.e. can I force libccur_fbsched to show up as "/usr/lib/libccur_fbsched.a" and not as "-Wl,-Bstatic -lccur_fbsched -Wl,-Bdynamic"?

(0039715)
Anthony Ette (reporter)
2015-10-31 18:13

I've found that if I instead use the syntax below, I can force the generated link command to use simply "/usr/lib/libccur_fbsched.a" although I don't know if this is the recommended way of doing things. I thought FIND_LIBRARY was supposed to be used here although I just can't seem to control its behavior well enough?

ADD_LIBRARY(libccur_fbsched STATIC IMPORTED)
SET_PROPERTY(TARGET libccur_fbsched PROPERTY IMPORTED_LOCATION ${USR_LIB}/libccur_fbsched${LIBEXT})
TARGET_LINK_LIBRARIES(
    ec_interface
    ${libshm}
    libccur_fbsched
)

(0039718)
Brad King (manager)
2015-11-02 08:52

See https://cmake.org/cmake/help/v3.3/policy/CMP0060.html [^] for an explanation of this historical behavior. Set the policy to NEW to always get the full path as desired.

(0040953)
Robert Maynard (manager)
2016-05-02 08:30

Closing resolved issues that have not been updated in more than 4 months.

Issue History
Date Modified	Username	Field	Change
2015-10-31 14:46	Anthony Ette	New Issue
2015-10-31 14:54	Anthony Ette	Note Added: 0039713
2015-10-31 14:58	Anthony Ette	Note Added: 0039714
2015-10-31 18:13	Anthony Ette	Note Added: 0039715
2015-11-02 08:52	Brad King	Note Added: 0039718
2015-11-02 08:53	Brad King	Status	new => resolved
2015-11-02 08:53	Brad King	Resolution	open => no change required
2016-05-02 08:30	Robert Maynard	Note Added: 0040953
2016-05-02 08:30	Robert Maynard	Status	resolved => closed

Notes
(0039713) Anthony Ette (reporter) 2015-10-31 14:54	Specific example: PROJECT(ec_interface) # static arhive #1 FILE(TO_CMAKE_PATH $ENV{LIB_INCL_DIR} LIB_INCL) FIND_LIBRARY(libshm NAMES shm PATHS ${LIB_D} NO_DEFAULT_PATH) MESSAGE("libshm: " ${libshm}) # static archive 0000002 FILE(TO_CMAKE_PATH /usr/lib USR_LIB) FIND_LIBRARY(libccur_fbsched NAMES libccur_fbsched.a PATHS ${USR_LIB} NO_DEFAULT_PATH) MESSAGE("libccur_fbsched: " ${libccur_fbsched}) SET(SOURCES ec_interface.cpp) TARGET_LINK_LIBRARIES(ec_interface ${libshm} ${libccur_fbsched}) Notice in the resulting linker command below how libshm and libccur_fbsched are handled very differently, why is this?: /usr/bin/g++ -O3 -DNDEBUG CMakeFiles/ec_interface.dir/ec_interface_w.cpp.o CMakeFiles/ec_interface.dir/ec_interface.cpp.o CMakeFiles/ec_interface.dir/resolver.c.o -o ../../../../ec_interface -rdynamic /sim/lib/v67/ihawk/libshm.a -Wl,-Bstatic -lccur_fbsched -Wl,-Bdynamic

(0039714) Anthony Ette (reporter) 2015-10-31 14:58	I guess it's also important to note that in LIB_D, only .a files exist (i.e. there is only a libshm.a and no libshm.so file). However, in /usr/lib, there are multiple files by the same name with differenet suffixes (e.g. libccur_fbsched.a, libccur_fbsched.so, etc.). That is why I am specifying the ".a" explicitly in the FIND_LIBRARY command for libccur_fbsched in an attempt to force it to pick up the static archive and not the dynamic ones. The message I'm printing seems to indicate it is using the static, so I still don't understand the resulting link command. How fine tuned of control do I have over the resulting link command? I.e. can I force libccur_fbsched to show up as "/usr/lib/libccur_fbsched.a" and not as "-Wl,-Bstatic -lccur_fbsched -Wl,-Bdynamic"?

(0039715) Anthony Ette (reporter) 2015-10-31 18:13	I've found that if I instead use the syntax below, I can force the generated link command to use simply "/usr/lib/libccur_fbsched.a" although I don't know if this is the recommended way of doing things. I thought FIND_LIBRARY was supposed to be used here although I just can't seem to control its behavior well enough? ADD_LIBRARY(libccur_fbsched STATIC IMPORTED) SET_PROPERTY(TARGET libccur_fbsched PROPERTY IMPORTED_LOCATION ${USR_LIB}/libccur_fbsched${LIBEXT}) TARGET_LINK_LIBRARIES( ec_interface ${libshm} libccur_fbsched )

(0039718) Brad King (manager) 2015-11-02 08:52	See https://cmake.org/cmake/help/v3.3/policy/CMP0060.html [^] for an explanation of this historical behavior. Set the policy to NEW to always get the full path as desired.

(0040953) Robert Maynard (manager) 2016-05-02 08:30	Closing resolved issues that have not been updated in more than 4 months.

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