[linux-next:master 11837/12788] arch/sh/boot/compressed/../../lib/ashldi3.c:6:11: warning: no previous prototype for '__ashldi3'

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head:   26ada2d1f143b558aa64c68f87c9f1335c1226eb
commit: 7ec713058f2191d7632d9f49b6ca290ab5cbf1ed [11837/12788] sh: boot: avoid unneeded rebuilds under arch/sh/boot/compressed/
config: sh-randconfig-r035-20210301 (attached as .config)
compiler: sh4-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=7ec713058f2191d7632d9f49b6ca290ab5cbf1ed
        git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
        git fetch --no-tags linux-next master
        git checkout 7ec713058f2191d7632d9f49b6ca290ab5cbf1ed
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=sh 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All warnings (new ones prefixed by >>):

   In file included from arch/sh/boot/compressed/ashldi3.c:2:

quoted

arch/sh/boot/compressed/../../lib/ashldi3.c:6:11: warning: no previous prototype for '__ashldi3' [-Wmissing-prototypes]

       6 | long long __ashldi3(long long u, word_type b)
         |           ^~~~~~~~~


vim +/__ashldi3 +6 arch/sh/boot/compressed/../../lib/ashldi3.c

1aad54a99b6ce3 Paul Mundt 2008-11-18   5  
1aad54a99b6ce3 Paul Mundt 2008-11-18  @6  long long __ashldi3(long long u, word_type b)
1aad54a99b6ce3 Paul Mundt 2008-11-18   7  {
1aad54a99b6ce3 Paul Mundt 2008-11-18   8  	DWunion uu, w;
1aad54a99b6ce3 Paul Mundt 2008-11-18   9  	word_type bm;
1aad54a99b6ce3 Paul Mundt 2008-11-18  10  
1aad54a99b6ce3 Paul Mundt 2008-11-18  11  	if (b == 0)
1aad54a99b6ce3 Paul Mundt 2008-11-18  12  		return u;
1aad54a99b6ce3 Paul Mundt 2008-11-18  13  
1aad54a99b6ce3 Paul Mundt 2008-11-18  14  	uu.ll = u;
1aad54a99b6ce3 Paul Mundt 2008-11-18  15  	bm = 32 - b;
1aad54a99b6ce3 Paul Mundt 2008-11-18  16  
1aad54a99b6ce3 Paul Mundt 2008-11-18  17  	if (bm <= 0) {
1aad54a99b6ce3 Paul Mundt 2008-11-18  18  		w.s.low = 0;
1aad54a99b6ce3 Paul Mundt 2008-11-18  19  		w.s.high = (unsigned int) uu.s.low << -bm;
1aad54a99b6ce3 Paul Mundt 2008-11-18  20  	} else {
1aad54a99b6ce3 Paul Mundt 2008-11-18  21  		const unsigned int carries = (unsigned int) uu.s.low >> bm;
1aad54a99b6ce3 Paul Mundt 2008-11-18  22  
1aad54a99b6ce3 Paul Mundt 2008-11-18  23  		w.s.low = (unsigned int) uu.s.low << b;
1aad54a99b6ce3 Paul Mundt 2008-11-18  24  		w.s.high = ((unsigned int) uu.s.high << b) | carries;
1aad54a99b6ce3 Paul Mundt 2008-11-18  25  	}
1aad54a99b6ce3 Paul Mundt 2008-11-18  26  
1aad54a99b6ce3 Paul Mundt 2008-11-18  27  	return w.ll;
1aad54a99b6ce3 Paul Mundt 2008-11-18  28  }
1aad54a99b6ce3 Paul Mundt 2008-11-18  29  

:::::: The code at line 6 was first introduced by commit
:::::: 1aad54a99b6ce316c851ba99b2efe41998cfd37d sh: Migrate necessary libgcc bits in to arch/sh/lib for SUPERH32.

:::::: TO: Paul Mundt [off-list ref]
:::::: CC: Paul Mundt [off-list ref]

---
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