| Message ID | 53B28365.1010508@codesourcery.com |
|---|---|
| State | New |
| Headers | show |
Luis Machado <lgustavo@codesourcery.com> writes: > For PowerPC 32-bit though, the small initialized global int variable > is sent to the .sdata section as an optimization. Since there is no > more data to store, the .data section doesn't get created. > > GDB complains about the lack of such a section and expect doesn't like > seeing that warning, which results in a couple failures for powerpc. Hmm, seems like a silly thing to complain about ... > One of them: > > [snip] > add-symbol-file gdb.base/code_elim2 0x200000 -s .data 0x210000 -s .bss 0x220000^M > add symbol table from file "gdb.d/gdb.base/code_elim2" at^M > .text_addr = 0x200000^M > .data_addr = 0x210000^M > .bss_addr = 0x220000^M > (y or n) y^M > Reading symbols from gdb.base/code_elim2...warning: section .data not > found in gdb.base/code_elim2^M > done.^M > (gdb) FAIL: gdb.base/code_elim.exp: order1: add-symbol-file code_elim2 > 0x200000 > > I have tweaked the testcase sources a little to hold a bigger > initialized global variable, forcing the linker to create a regular > .data section in order to prevent GDB's warning. The testcase still > runs fine, but now PowerPC 32-bit sees full passes on this one. Is tweaking the testcase really the best approach here? Shouldn't GDB just be less picky?
On 07/08/2014 02:52 AM, Samuel Bronson wrote: > Luis Machado <lgustavo@codesourcery.com> writes: > >> For PowerPC 32-bit though, the small initialized global int variable >> is sent to the .sdata section as an optimization. Since there is no >> more data to store, the .data section doesn't get created. >> >> GDB complains about the lack of such a section and expect doesn't like >> seeing that warning, which results in a couple failures for powerpc. > > Hmm, seems like a silly thing to complain about ... > >> One of them: >> >> [snip] >> add-symbol-file gdb.base/code_elim2 0x200000 -s .data 0x210000 -s .bss 0x220000^M >> add symbol table from file "gdb.d/gdb.base/code_elim2" at^M >> .text_addr = 0x200000^M >> .data_addr = 0x210000^M >> .bss_addr = 0x220000^M >> (y or n) y^M >> Reading symbols from gdb.base/code_elim2...warning: section .data not >> found in gdb.base/code_elim2^M >> done.^M >> (gdb) FAIL: gdb.base/code_elim.exp: order1: add-symbol-file code_elim2 >> 0x200000 >> >> I have tweaked the testcase sources a little to hold a bigger >> initialized global variable, forcing the linker to create a regular >> .data section in order to prevent GDB's warning. The testcase still >> runs fine, but now PowerPC 32-bit sees full passes on this one. > > Is tweaking the testcase really the best approach here? Shouldn't GDB > just be less picky? > Either solution is fine with me, but the warning is actually somewhat informative since the .data section is relatively common. The testcase, on the other hand, is not designed to behave the same in all architectures. Luis
On 07/08/2014 06:47 AM, Luis Machado wrote: > On 07/08/2014 02:52 AM, Samuel Bronson wrote: >> Luis Machado <lgustavo@codesourcery.com> writes: >>> add-symbol-file gdb.base/code_elim2 0x200000 -s .data 0x210000 -s .bss 0x220000^M ^^^^^^^^^^^^^^ [snip] >>> Reading symbols from gdb.base/code_elim2...warning: section .data not >>> found in gdb.base/code_elim2^M [snip] >> Is tweaking the testcase really the best approach here? Shouldn't GDB >> just be less picky? >> > > Either solution is fine with me, but the warning is actually somewhat > informative since the .data section is relatively common. That doesn't make sense in this context. GDB is not being picky -- the warning is coming out because the user _explicitly_ specified an address for the .data section, not because .data is special in any way.
2014-07-01 Luis Machado <lgustavo@codesourcery.com> * gdb.base/code_elim2.c (my_global_array): New global variable. (my_global_func): Use global variable. diff --git a/gdb/testsuite/gdb.base/code_elim2.c b/gdb/testsuite/gdb.base/code_elim2.c index 64ecc04..3eb8d5c 100644 --- a/gdb/testsuite/gdb.base/code_elim2.c +++ b/gdb/testsuite/gdb.base/code_elim2.c @@ -15,6 +15,9 @@ You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ +/* Declare a global variable of reasonable size to make sure the .data section + is created, preventing a warning from GDB when manually loading symbols. */ +int my_global_array[6] = {4, 8, 15, 16, 23, 42}; int my_global_symbol = 42; static int my_static_symbol; @@ -28,7 +31,7 @@ main () int my_global_func () { - my_static_symbol = my_global_symbol; - my_global_symbol = my_static_symbol + my_global_symbol; + my_static_symbol = my_global_symbol + my_global_array[6]; + my_global_symbol = my_static_symbol + my_global_symbol + my_global_array[3]; return my_global_symbol; }
Hi, Another case of slight variations between targets and compiler options. gdb.base/code_elim.exp assumes the linker generates the same sections for all architectures. For x86, this works fine and the testcase binary code_elim2 contains the .data section to hold our initialized global int variable. For PowerPC 32-bit though, the small initialized global int variable is sent to the .sdata section as an optimization. Since there is no more data to store, the .data section doesn't get created. GDB complains about the lack of such a section and expect doesn't like seeing that warning, which results in a couple failures for powerpc. One of them: [snip] add-symbol-file gdb.base/code_elim2 0x200000 -s .data 0x210000 -s .bss 0x220000^M add symbol table from file "gdb.d/gdb.base/code_elim2" at^M .text_addr = 0x200000^M .data_addr = 0x210000^M .bss_addr = 0x220000^M (y or n) y^M Reading symbols from gdb.base/code_elim2...warning: section .data not found in gdb.base/code_elim2^M done.^M (gdb) FAIL: gdb.base/code_elim.exp: order1: add-symbol-file code_elim2 0x200000 I have tweaked the testcase sources a little to hold a bigger initialized global variable, forcing the linker to create a regular .data section in order to prevent GDB's warning. The testcase still runs fine, but now PowerPC 32-bit sees full passes on this one. I thought about tweaking the optimization options, but that would need to be target-specific, which is more cumbersome. Luis