[cdt-dev] Changing toolchain default values via CDT extension point

["Stud" <Stud@xxxxxxxx>]

I tried to implement an own toolchain (using 'arm-elf-gcc' instead of 'gcc' (both in Cygwin)) by writing a Plugin using the extension point "org.eclipse.cdt.managedbuilder.core.ManagedBuildInfo" of cdt_2.0.0.

I simply wanted to create a new 'Managed Make C Project' - target with different default values for the tool-chain.

Finally I had this 'plugin.xml':

<?xml version="1.0" encoding="UTF-8"?>
<?eclipse version="3.0"?>
<plugin
   id="at.medek.unc20.eclipse.cdt.develop"
   name="UNC20 Developer&apos;s Plugin"
   version="1.0.0"
   provider-name="Medek &amp; Schörner Ges.m.b.H">

   <runtime>
      <library name="unc20_cdt.jar">
         <export name="*"/>
      </library>
   </runtime>
   <requires>
      <import plugin="org.eclipse.cdt.managedbuilder.ui"/>
      <import plugin="org.eclipse.cdt.managedbuilder.core"/>
   </requires>
   <extension
         id="at.medek.unc20.eclipse.cdt.develop.build"
         name="UNC20 CDT Develop Build"
         point="org.eclipse.cdt.managedbuilder.core.ManagedBuildInfo">
         
      <target
            name="Binary for UNC20 (Cygwin on Windows)"
            id="cdt.managedbuild.target.gnu.cygwin.test"
            isTest="false"
            defaultExtension="elf"
            scannerInfoCollector="org.eclipse.cdt.managedbuilder.internal.scannerconfig.DefaultGnuWinScannerInfoCollector"
            makefileGenerator="org.eclipse.cdt.managedbuilder.makegen.gnu.GnuMakefileGenerator"
            isAbstract="false"
            binaryParser="org.eclipse.cdt.core.PE"
            osList="win32"
            parent="cdt.managedbuild.target.gnu">
         <configuration
               name="Debug"
               id="cdt.managedbuild.config.gnu.unc20.cygwin.windows.debug">
            <toolReference
                  command="arm-elf-gcc"
                  id="cdt.managedbuild.tool.gnu.c.compiler">
               <optionReference
                     defaultValue="gnu.c.optimization.level.none"
                     id="gnu.c.compiler.option.optimization.level">
               </optionReference>
               <optionReference
                     defaultValue="gnu.c.debugging.level.default"
                     id="gnu.c.compiler.option.debugging.level">
               </optionReference>
               <optionReference
                     defaultValue="false"
                     id="gnu.c.compiler.option.warnings.allwarn">
               </optionReference>
               <optionReference
                     defaultValue="-c -mbig-endian -mcpu=arm7tdmi"
                     id="gnu.c.compiler.option.misc.other">
               </optionReference>
            </toolReference>
            <toolReference
                  command="arm-elf-gcc"
                  output="o"
                  id="cdt.managedbuild.tool.gnu.assembler">
               <optionReference
                     defaultValue="-c -mbig-endian -mcpu=arm7tdmi -Wall"
                     id="gnu.both.asm.option.flags">
               </optionReference>
            </toolReference>
            <toolReference
                  outputs="elf"
                  command="arm-elf-gcc"
                  id="cdt.managedbuild.tool.gnu.c.linker">
               <optionReference
                     defaultValue="true"
                     id="gnu.c.link.option.nostart">
               </optionReference>
               <optionReference
                     defaultValue="-mbig-endian -mcpu=arm7tdmi -L.. -Tdebug.ld"
                     id="gnu.c.link.option.ldflags">
               </optionReference>
            </toolReference>
         </configuration>
         <configuration
               name="Release"
               id="cdt.managedbuild.config.gnu.unc20.cygwin.windows.release">
            <toolReference
                  command="arm-elf-gcc"
                  id="cdt.managedbuild.tool.gnu.c.compiler">
               <optionReference
                     defaultValue="gnu.c.optimization.level.none"
                     id="gnu.c.compiler.option.optimization.level">
               </optionReference>
               <optionReference
                     defaultValue="gnu.c.debugging.level.default"
                     id="gnu.c.compiler.option.debugging.level">
               </optionReference>
               <optionReference
                     defaultValue="false"
                     id="gnu.c.compiler.option.warnings.allwarn">
               </optionReference>
               <optionReference
                     defaultValue="-mbig-endian -mcpu=arm7tdmi"
                     id="gnu.c.compiler.option.misc.other">
               </optionReference>
            </toolReference>
            <toolReference
                  command="arm-elf-gcc"
                  output="o"
                  id="cdt.managedbuild.tool.gnu.assembler">
               <optionReference
                     defaultValue="-c -mbig-endian -mcpu=arm7tdmi -Wall"
                     id="gnu.both.asm.option.flags">
               </optionReference>
            </toolReference>
            <toolReference
                  outputs="elf"
                  command="arm-elf-gcc"
                  id="cdt.managedbuild.tool.gnu.c.linker">
               <optionReference
                     defaultValue="true"
                     id="gnu.c.link.option.nostart">
               </optionReference>
               <optionReference
                     defaultValue="-mbig-endian -mcpu=arm7tdmi -L.. -Trelease.ld"
                     id="gnu.c.link.option.ldflags">
               </optionReference>
            </toolReference>
         </configuration>
         <toolReference
               id="cdt.managedbuild.tool.gnu.c.linker">
         </toolReference>
      </target>
   </extension>
</plugin>

The corresponding UI-toolchain was exactly what I wanted, but it did not work correctly.

My files were:

init.S
main.c
release.ld
debug.ld

My build output for the 'Debug' configuration was:

**** Incremental build of configuration Debug for project test2 ****

make -k all 
Building file: ../main.c
arm-elf-gcc -O0 -g -c -mbig-endian -mcpu=arm7tdmi -o main.o ../main.c Finished building: ../main.c
 
Building file: ../init.S
arm-elf-gcc -c -mbig-endian -mcpu=arm7tdmi -Wall -o init.o ../init.S Finished building: ../init.S
 
Building target: test2.elf
null null  test2.elf main.o      init.o  
make: null: Command not found
make: *** [test2.elf] Error 127
make: Target `all' not remade because of errors.
Build complete for project test2

Finally I was able to find a workaround for this problem. In the 'Properties'/'C/C++ Build' project folder I pressed the button 'Restore Defaults' and it worked. (see below)

**** Incremental build of configuration Debug for project test2 ****

make -k all 
Building target: test2.elf
arm-elf-gcc -nostartfiles -mbig-endian -mcpu=arm7tdmi -L.. -Tdebug.ld -o test2.elf main.o      init.o  
Finished building: test2.elf
Build complete for project test2

In this case the initial values of the tool-chain seemed to be not identical with the 'default' values.

The same problem happened with the 'release' configuration. The workaround is the same.

Is there something wrong with my 'plugin.xml'?