On 04/28/2013 10:59 PM, Rusty Russell wrote: > Tom Rini <trini@xxxxxx> writes: > >> Recent gcc's may place functions into the .text.unlikely section and we >> need to check this section as well for section mismatches now otherwise >> we may have false negatives for this test. > > Hmm, I don't think it's all that recent, is it? I can find it back to > gcc 4.0.4: > > `-freorder-functions' > Reorder functions in the object file in order to improve code > locality. This is implemented by using special subsections > `.text.hot' for most frequently executed functions and > `.text.unlikely' for unlikely executed functions. Reordering is > done by the linker so object file format must support named > sections and linker must place them in a reasonable way. > > Also profile feedback must be available in to make this option > effective. See `-fprofile-arcs' for details. > > Enabled at levels `-O2', `-O3', `-Os'. > > The comment is the same in in gcc 4.7. > > So is your real issue that this section is generated with > -fprofile-arcs, or has something changed with gcc 4.8, or...? I've started seeing this with Linaro based 4.7 toolchains. I can go back through their releases and see when it starts showing up there if it helps. I didn't add .text.hot as I didn't have that section at all, fwiw. -- Tom -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
