Compile warnings on Strawberry Perl 5.26

[pali]

https://travis-ci.org/Dual-Life/Devel-PPPort/jobs/546411081

C:\STRAWB~1\perl\lib\CORE/hv_func.h: In function 'S_perl_hash_oaathu_siphash_1_3':
C:\STRAWB~1\perl\lib\CORE/hv_func.h:315:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[15];
             ~~~~~^~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:316:9: note: here
         case 15:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:319:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[14];
             ~~~~~^~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:320:9: note: here
         case 14:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:323:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[13];
             ~~~~~^~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:324:9: note: here
         case 13:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:327:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[12];
             ~~~~~^~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:328:9: note: here
         case 12:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:331:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[11];
             ~~~~~^~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:332:9: note: here
         case 11:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:335:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[10];
             ~~~~~^~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:336:9: note: here
         case 10:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:339:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[9];
             ~~~~~^~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:340:9: note: here
         case 9:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:343:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[8];
             ~~~~~^~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:344:9: note: here
         case 8:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:347:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[7];
             ~~~~~^~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:348:9: note: here
         case 7:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:351:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[6];
             ~~~~~^~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:352:9: note: here
         case 6:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:355:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[5];
             ~~~~~^~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:356:9: note: here
         case 5:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:359:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[4];
             ~~~~~^~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:360:9: note: here
         case 4:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:363:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[3];
             ~~~~~^~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:364:9: note: here
         case 3:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:367:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[2];
             ~~~~~^~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:368:9: note: here
         case 2:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:371:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[1];
             ~~~~~^~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:372:9: note: here
         case 1:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:375:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
             hash += str[0];
             ~~~~~^~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:376:9: note: here
         case 0:
         ^~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h: In function 'S_perl_hash_siphash_1_3':
C:\STRAWB~1\perl\lib\CORE/hv_func.h:218:13: warning: this statement may fall through [-Wimplicit-fallthrough=]
   case 7: b |= ( ( U64 )in[ 6] )  << 48;    \
           ~~^~~~~~~~~~~~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:242:1: note: in expansion of macro 'PERL_SIPHASH_FNC'
 PERL_SIPHASH_FNC(
 ^~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:219:3: note: here
   case 6: b |= ( ( U64 )in[ 5] )  << 40;    \
   ^
C:\STRAWB~1\perl\lib\CORE/hv_func.h:242:1: note: in expansion of macro 'PERL_SIPHASH_FNC'
 PERL_SIPHASH_FNC(
 ^~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:219:13: warning: this statement may fall through [-Wimplicit-fallthrough=]
   case 6: b |= ( ( U64 )in[ 5] )  << 40;    \
           ~~^~~~~~~~~~~~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:242:1: note: in expansion of macro 'PERL_SIPHASH_FNC'
 PERL_SIPHASH_FNC(
 ^~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:220:3: note: here
   case 5: b |= ( ( U64 )in[ 4] )  << 32;    \
   ^
C:\STRAWB~1\perl\lib\CORE/hv_func.h:242:1: note: in expansion of macro 'PERL_SIPHASH_FNC'
 PERL_SIPHASH_FNC(
 ^~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:220:13: warning: this statement may fall through [-Wimplicit-fallthrough=]
   case 5: b |= ( ( U64 )in[ 4] )  << 32;    \
           ~~^~~~~~~~~~~~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:242:1: note: in expansion of macro 'PERL_SIPHASH_FNC'
 PERL_SIPHASH_FNC(
 ^~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:221:3: note: here
   case 4: b |= ( ( U64 )in[ 3] )  << 24;    \
   ^
C:\STRAWB~1\perl\lib\CORE/hv_func.h:242:1: note: in expansion of macro 'PERL_SIPHASH_FNC'
 PERL_SIPHASH_FNC(
 ^~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:221:13: warning: this statement may fall through [-Wimplicit-fallthrough=]
   case 4: b |= ( ( U64 )in[ 3] )  << 24;    \
           ~~^~~~~~~~~~~~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:242:1: note: in expansion of macro 'PERL_SIPHASH_FNC'
 PERL_SIPHASH_FNC(
 ^~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:222:3: note: here
   case 3: b |= ( ( U64 )in[ 2] )  << 16;    \
   ^
C:\STRAWB~1\perl\lib\CORE/hv_func.h:242:1: note: in expansion of macro 'PERL_SIPHASH_FNC'
 PERL_SIPHASH_FNC(
 ^~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:222:13: warning: this statement may fall through [-Wimplicit-fallthrough=]
   case 3: b |= ( ( U64 )in[ 2] )  << 16;    \
           ~~^~~~~~~~~~~~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:242:1: note: in expansion of macro 'PERL_SIPHASH_FNC'
 PERL_SIPHASH_FNC(
 ^~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:223:3: note: here
   case 2: b |= ( ( U64 )in[ 1] )  <<  8;    \
   ^
C:\STRAWB~1\perl\lib\CORE/hv_func.h:242:1: note: in expansion of macro 'PERL_SIPHASH_FNC'
 PERL_SIPHASH_FNC(
 ^~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:223:13: warning: this statement may fall through [-Wimplicit-fallthrough=]
   case 2: b |= ( ( U64 )in[ 1] )  <<  8;    \
           ~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:242:1: note: in expansion of macro 'PERL_SIPHASH_FNC'
 PERL_SIPHASH_FNC(
 ^~~~~~~~~~~~~~~~
C:\STRAWB~1\perl\lib\CORE/hv_func.h:224:3: note: here
   case 1: b |= ( ( U64 )in[ 0] ); break;    \
   ^
C:\STRAWB~1\perl\lib\CORE/hv_func.h:242:1: note: in expansion of macro 'PERL_SIPHASH_FNC'
 PERL_SIPHASH_FNC(
 ^~~~~~~~~~~~~~~~

[khwilliamson]

@pali I don't know how to fix this. The code is from a core header, and blead still has similar code. So it is probably warning there too.

[pali]

Looks like that it is needed to understand what that warning exactly means and why is not throwed on linux builds, which uses also gcc compiler. Maybe it is related to 32 vs 64 bit builds? Or what is difference? (I do not know)