---------------------------------------- > CC: jwakely....@gmail.com; renato.go...@linaro.org; gcc@gcc.gnu.org > From: pins...@gmail.com > Subject: Re: Compiler warnings while compiling gcc with clang > Date: Tue, 5 May 2015 20:19:04 -0700 > To: hiradi...@msn.com > > > > > >> On May 5, 2015, at 8:13 PM, Aditya K <hiradi...@msn.com> wrote: >> >> So, I analyzed other warnings and following is the list of relevant warning >> that I could collect. Hope this is useful. >> >> >> gcc/ipa-icf.c:508:12: warning: logical not is only applied to the left hand >> side of this comparison >> ../../gcc/ipa-icf.c:508:12: warning: logical not is only applied to the left >> hand side of this comparison [-Wlogical-not-parentheses] >> if ((!type == FUNC || address || !opt_for_fn (decl, optimize_size)) >> >> gcc/expr.c:5271:9: warning: comparison of constant -1 with expression of >> type 'unsigned int' is always false >> [-Wtautological-constant-out-of-range-compare] >> ../../gcc/expr.c:5271:9: warning: comparison of constant -1 with expression >> of type 'unsigned int' is always false >> [-Wtautological-constant-out-of-range-compare] >> if (!SUBREG_CHECK_PROMOTED_SIGN (target, >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> There was a similar bug posted some time ago >> (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61271) >> -------------------------------------------------------------------------------------------------------------------------------- >> >> gcc/reload1.c:470:28: warning: incrementing expression of type bool is >> deprecated [-Wdeprecated-increment-bool] >> ../../gcc/reload1.c:470:28: warning: incrementing expression of type bool is >> deprecated [-Wdeprecated-increment-bool] >> spill_indirect_levels++; >> ~~~~~~~~~~~~~~~~~~~~~^ >> >> Seems like for this bug we need to change the declaration of >> >> bool this_target_reload::x_spill_indirect_levels to an int. Even the comment >> there mentions that this variable might take >> other integral values. >> >> /* Nonzero if indirect addressing is supported on the machine; this means >> that spilling (REG n) does not require reloading it into a register in >> order to do (MEM (REG n)) or (MEM (PLUS (REG n) (CONST_INT c))). The >> value indicates the level of indirect addressing supported, e.g., two >> means that (MEM (MEM (REG n))) is also valid if (REG n) does not get >> a hard register. */ >> bool x_spill_indirect_levels; >> >> >> -------------------------------------------------------------------------------------------------------------------------------- >> >> gcc/rtlanal.c:5573:23: warning: array index 1 is past the end of the array >> (which contains 1 element) [-Warray-bounds] >> ../../gcc/rtlanal.c:5573:23: warning: array index 1 is past the end of the >> array (which contains 1 element) [-Warray-bounds] >> *second = GEN_INT (CONST_DOUBLE_HIGH (value)); >> ^~~~~~~~~~~~~~~~~~~~~~~~~ > > These warnings are bogus due to the array being the last element of the > structure. > > Please file that with clang. >
IIRC, C++ does not allow flexible array members. Thanks, -Aditya > Thanks, > Andrew > > > >> >> ../../gcc/rtl.h:1757:30: note: expanded from macro 'CONST_DOUBLE_HIGH' >> #define CONST_DOUBLE_HIGH(r) XCMWINT (r, 1, CONST_DOUBLE, VOIDmode) >> ^ ~ >> ../../gcc/rtl.h:1123:36: note: expanded from macro 'XCMWINT' >> #define XCMWINT(RTX, N, C, M) ((RTX)->u.hwint[N]) >> ^ >> ../../gcc/rtl.h:3193:51: note: expanded from macro 'GEN_INT' >> #define GEN_INT(N) gen_rtx_CONST_INT (VOIDmode, (N)) >> ^ >> ../../gcc/rtl.h:397:5: note: array 'hwint' declared here >> HOST_WIDE_INT hwint[1]; >> ^ >> ../../gcc/hwint.h:54:26: note: expanded from macro 'HOST_WIDE_INT' >> # define HOST_WIDE_INT long >> ^ >> >> -------------------------------------------------------------------------------------------------------------------------------- >> >> gcc/vec.h:1048:10: warning: offset of on non-POD type 'vec_embedded' (aka >> 'vec<c_expr::id_tab, va_heap, vl_embed>') [-Winvalid-offsetof] >> ../../gcc/vec.h:1048:10: warning: offset of on non-POD type 'vec_embedded' >> (aka 'vec<std::pair<expr_hash_elt *, expr_hash_elt *>, va_heap, vl_embed>') >> [-Winvalid-offsetof] >> return offsetof (vec_embedded, m_vecdata) + alloc * sizeof (T); >> ^ ~~~~~~~~~ >> /home/hiraditya/work/llvm/install-release/bin/../lib/clang/3.7.0/include/stddef.h:120:24: >> note: expanded from macro 'offsetof' >> #define offsetof(t, d) __builtin_offsetof(t, d) >> >> >> -------------------------------------------------------------------------------------------------------------------------------- >> >> genrtl.h:435:3: warning: array index 1 is past the end of the array (which >> contains 1 element) [-Warray-bounds] >> ./genrtl.h:435:3: warning: array index 1 is past the end of the array (which >> contains 1 element) [-Warray-bounds] >> XWINT (rt, 1) = arg1; >> ^ ~ >> ../../gcc/rtl.h:1120:29: note: expanded from macro 'XWINT' >> #define XWINT(RTX, N) ((RTX)->u.hwint[N]) >> ^ >> ../../gcc/rtl.h:397:5: note: array 'hwint' declared here >> HOST_WIDE_INT hwint[1]; >> ^ >> ../../gcc/hwint.h:54:26: note: expanded from macro 'HOST_WIDE_INT' >> # define HOST_WIDE_INT long >> >> -------------------------------------------------------------------------------------------------------------------------------- >> >> gcc/final.c:3957:8: warning: array index 1 is past the end of the array >> (which contains 1 element) [-Warray-bounds] >> ../../gcc/final.c:3957:8: warning: array index 1 is past the end of the >> array (which contains 1 element) [-Warray-bounds] >> if (CONST_DOUBLE_HIGH (x)) >> ^~~~~~~~~~~~~~~~~~~~~ >> ../../gcc/rtl.h:1757:30: note: expanded from macro 'CONST_DOUBLE_HIGH' >> #define CONST_DOUBLE_HIGH(r) XCMWINT (r, 1, CONST_DOUBLE, VOIDmode) >> ^ ~ >> ../../gcc/rtl.h:1123:36: note: expanded from macro 'XCMWINT' >> #define XCMWINT(RTX, N, C, M) ((RTX)->u.hwint[N]) >> ^ >> ../../gcc/rtl.h:397:5: note: array 'hwint' declared here >> HOST_WIDE_INT hwint[1]; >> ^ >> ../../gcc/hwint.h:54:26: note: expanded from macro 'HOST_WIDE_INT' >> # define HOST_WIDE_INT long >> ^ >> >> -------------------------------------------------------------------------------------------------------------------------------- >> >> gcc/cse.c:6171:38: warning: array index 1 is past the end of the array >> (which contains 1 element) [-Warray-bounds] >> ../../gcc/cse.c:6171:38: warning: array index 1 is past the end of the array >> (which contains 1 element) [-Warray-bounds] >> || (CONST_DOUBLE_P (new_rtx) && CONST_DOUBLE_HIGH (new_rtx)>= 0)) >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~ >> ../../gcc/rtl.h:1757:30: note: expanded from macro 'CONST_DOUBLE_HIGH' >> #define CONST_DOUBLE_HIGH(r) XCMWINT (r, 1, CONST_DOUBLE, VOIDmode) >> ^ ~ >> ../../gcc/rtl.h:1123:36: note: expanded from macro 'XCMWINT' >> #define XCMWINT(RTX, N, C, M) ((RTX)->u.hwint[N]) >> ^ >> ../../gcc/rtl.h:397:5: note: array 'hwint' declared here >> HOST_WIDE_INT hwint[1]; >> ^ >> ../../gcc/hwint.h:54:26: note: expanded from macro 'HOST_WIDE_INT' >> # define HOST_WIDE_INT long >> ^ >> >> -------------------------------------------------------------------------------------------------------------------------------- >> >> gcc/gcov-tool.c:225:7: warning: variable 'ret' is used uninitialized >> whenever 'if' condition is false [-Wsometimes-uninitialized] >> gcc/gcov-tool.c:493:7: warning: variable 'ret' is used uninitialized >> whenever 'if' condition is false [-Wsometimes-uninitialized] >> ../../gcc/gcov-tool.c:225:7: warning: variable 'ret' is used uninitialized >> whenever 'if' condition is false [-Wsometimes-uninitialized] >> if (argc - optind == 2) >> ^~~~~~~~~~~~~~~~~~ >> ../../gcc/gcov-tool.c:230:10: note: uninitialized use occurs here >> return ret; >> ^~~ >> ../../gcc/gcov-tool.c:225:3: note: remove the 'if' if its condition is >> always true >> if (argc - optind == 2) >> ^~~~~~~~~~~~~~~~~~~~~~~ >> ../../gcc/gcov-tool.c:196:10: note: initialize the variable 'ret' to silence >> this warning >> int ret; >> ^ >> = 0 >> ../../gcc/gcov-tool.c:493:7: warning: variable 'ret' is used uninitialized >> whenever 'if' condition is false [-Wsometimes-uninitialized] >> if (argc - optind == 2) >> ^~~~~~~~~~~~~~~~~~ >> ../../gcc/gcov-tool.c:498:10: note: uninitialized use occurs here >> return ret; >> ^~~ >> ../../gcc/gcov-tool.c:493:3: note: remove the 'if' if its condition is >> always true >> if (argc - optind == 2) >> ^~~~~~~~~~~~~~~~~~~~~~~ >> ../../gcc/gcov-tool.c:462:10: note: initialize the variable 'ret' to silence >> this warning >> int ret; >> ^ >> = 0 >> >> >> I think I can fix few of these if we want them to be fixed. >> For some e.g. ( gcc/gcov-tool.c:225:7: warning: array index 1 is past the >> end of the array (which contains 1 element) ), >> I have no idea what is the proper fix for them. >> >> -Aditya >> >> >>> Date: Tue, 5 May 2015 21:57:08 +0100 >>> Subject: Re: Compiler warnings while compiling gcc with clang >>> From: jwakely....@gmail.com >>> To: hiradi...@msn.com >>> CC: pins...@gmail.com; renato.go...@linaro.org; gcc@gcc.gnu.org >>> >>>> On 5 May 2015 at 12:39, Aditya K wrote: >>>> There are however, other differences between class and struct >>>> (http://stackoverflow.com/a/999810/811335) i.e., >>>> >>>> 1. In absence of an access-specifier for a base class, public is assumed >>>> when the derived class is declared struct and private is assumed when the >>>> class is declared class. >>> >>> Yes, everyone here knows that. That is only relevant to the definition >>> of the class, which can only occur once. For the purposes of >>> declarations that are not definitions there is no difference. >>> >>>> 2. class can be used in place of a typename to declare a template >>>> parameter, while the struct cannot. >>> >>> Completely irrelevant in this context. The use of 'class' in a >>> template parameter list has nothing to do with struct or class types, >>> nor forward declarations of struct or class types. >>
