cannot install apps on my xperia sp

[nirosh07098]

few days after buying my new xperia sp i could not install any app on it and it gives a error message as " Unknown error code during application install: "919" " . but after i upgrade it to 4.1.2 it was ok and i could install apps from play store. but now again i cannot install atleast same apps again. ( i removed them for a reason before) same error message appears. please help me..

i found it as kernel build error from the new. what can i do

https://gist.github.com/uberlaggydarwin/6292686#file-xperia-sp-kernel-build-error-L919

919 bionic/libm/upstream-freebsd/lib/msun/src/e_j0f.c:139:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]

[thined5]

I try to connect it in wifi on my friend and it works but i still want to use my 3g network because it is only my connection.. hope u can help me