[Bug debug/60524] New: Typedef information bypassed in dwarf2 function parameter information when it is 'const'

[wpk at culm dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60524

            Bug ID: 60524
           Summary: Typedef information bypassed in dwarf2 function
                    parameter information when it is 'const'
           Product: gcc
           Version: 4.8.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: debug
          Assignee: unassigned at gcc dot gnu.org
          Reporter: wpk at culm dot net

For following code:


typedef unsigned char Bar[12];
void foo(Bar *bar) {}
void fooconst(const Bar *bar) {}

compiled with gcc -gdwarf-2 -c, readelf -wi shows the foolowing dwarf-2 info:


For typedef Bar:

 <1><2d>: Abbrev Number: 2 (DW_TAG_typedef)
    <2e>   DW_AT_name        : Bar
    <32>   DW_AT_decl_file   : 1
    <33>   DW_AT_decl_line   : 1
    <34>   DW_AT_type        : <0x38>
 <1><38>: Abbrev Number: 3 (DW_TAG_array_type)
    <39>   DW_AT_type        : <0x4f>
    <3d>   DW_AT_sibling     : <0x48>



For 'foo' function:

 <1><56>: Abbrev Number: 6 (DW_TAG_subprogram)
(...)
    <58>   DW_AT_name        : foo
(...)
 <2><78>: Abbrev Number: 7 (DW_TAG_formal_parameter)
    <79>   DW_AT_name        : bar
(...)
    <7f>   DW_AT_type        : <0x87>
(...)
 <1><87>: Abbrev Number: 8 (DW_TAG_pointer_type)
    <88>   DW_AT_byte_size   : 8
    <89>   DW_AT_type        : <0x2d>

This points to DW_TAG_typedef for 'Bar'




But for 'fooconst':

 <1><8d>: Abbrev Number: 9 (DW_TAG_subprogram)
(...)
    <8f>   DW_AT_name        : (indirect string, offset: 0x5c): fooconst
(...)
 <2><af>: Abbrev Number: 7 (DW_TAG_formal_parameter)
    <b0>   DW_AT_name        : bar
(..)
    <b6>   DW_AT_type        : <0xbe>
(..)
 <1><be>: Abbrev Number: 8 (DW_TAG_pointer_type)
    <bf>   DW_AT_byte_size   : 8
    <c0>   DW_AT_type        : <0x38>

This points directly to unsigned char[12], completely bypassing typedef Bar
info. 


GCC version info:
Using built-in specs.
COLLECT_GCC=/usr/bin/gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/4.8/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro
4.8.1-10ubuntu9' --with-bugurl=file:///usr/share/doc/gcc-4.8/README.Bugs
--enable-languages=c,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr
--program-suffix=-4.8 --enable-shared --enable-linker-build-id
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--with-gxx-include-dir=/usr/include/c++/4.8 --libdir=/usr/lib --enable-nls
--with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug
--enable-libstdcxx-time=yes --enable-gnu-unique-object --enable-plugin
--with-system-zlib --disable-browser-plugin --enable-java-awt=gtk
--enable-gtk-cairo --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-4.8-amd64/jre
--enable-java-home --with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-4.8-amd64
--with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-4.8-amd64
--with-arch-directory=amd64 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar
--enable-objc-gc --enable-multiarch --disable-werror --with-arch-32=i686
--with-abi=m64 --with-multilib-list=m32,m64,mx32 --with-tune=generic
--enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu
--target=x86_64-linux-gnu
Thread model: posix
gcc version 4.8.1 (Ubuntu/Linaro 4.8.1-10ubuntu9)