126985 2014-01-14 07:39:38 -0800 Source/WTF/wtf/Atomics.h:300: Error: bad register name `%bpl' 2014-01-16 13:39:43 -0800 1 1 1 Unclassified WebKit Web Template Framework 528+ (Nightly build) Unspecified Unspecified RESOLVED FIXED P2 Normal --- 1 berto webkit-unassigned benjamin cmarcelo commit-queue David.Ronis oliver tpopela zan oldest_to_newest 967831 0 berto 2014-01-14 07:39:38 -0800 I'm having problems building the GTK+ port in i386. Looks like gcc is producing x86-64 registers here: inline bool weakCompareAndSwap(uint8_t* location, uint8_t expected, uint8_t newValue) { unsigned char result; asm volatile( "lock; cmpxchgb %3, %2\n\t" "sete %1" : "+a"(expected), "=q"(result), "+m"(*location) : "r"(newValue) : "memory" ); return result; } Here's the gcc output of the affected pre-processed source file: $ gcc -O1 -m32 --std=c++11 -c CodeBlock.ii ../Source/WTF/wtf/Atomics.h: Assembler messages: ../Source/WTF/wtf/Atomics.h:300: Error: bad register name `%bpl' ../Source/WTF/wtf/Atomics.h:300: Error: bad register name `%bpl' ../Source/WTF/wtf/Atomics.h:300: Error: bad register name `%dil' Adding -frename-registers seems to solve the problem. It also builds fine with clang. My understanding is that this is a gcc bug, however reading the upstream report http://gcc.gnu.org/bugzilla/show_bug.cgi?id=10153 and its duplicates suggests that the constraints in the function I pasted above might be wrong. 967905 1 zan 2014-01-14 10:26:07 -0800 *** Bug 126989 has been marked as a duplicate of this bug. *** 968046 2 David.Ronis 2014-01-14 14:35:21 -0800 I added -frename-registers to the build CFLAGS and CXXFLAGS. I get the exact same message as in my initial report: ./Source/WTF/wtf/Atomics.h: Assembler messages: ./Source/WTF/wtf/Atomics.h:300: Error: bad register name `%sil' 968707 3 221366 berto 2014-01-16 04:39:04 -0800 Created attachment 221366 Patch The problem is that with the "r" constraint we are telling gcc to put 'newValue' into any general register, which is then used as an operand for cmpxchgb. However in i386 not all registers allow access to their lower byte, which is what we need here. The "q" constraint ensures that in 32-bit mode only the a, b, c and d registers are used. 968708 4 commit-queue 2014-01-16 04:40:37 -0800 Attachment 221366 did not pass style-queue: Failed to run "['Tools/Scripts/check-webkit-style', '--diff-files', u'Source/WTF/ChangeLog', u'Source/WTF/wtf/Atomics.h', '--commit-queue']" exit_code: 1 ERROR: Source/WTF/wtf/Atomics.h:298: Wrong number of spaces before statement. (expected: 12) [whitespace/indent] [4] ERROR: Source/WTF/wtf/Atomics.h:298: Wrong number of spaces before statement. (expected: 12) [whitespace/indent] [4] Total errors found: 2 in 2 files If any of these errors are false positives, please file a bug against check-webkit-style. 968772 5 221366 ossy 2014-01-16 08:47:51 -0800 Comment on attachment 221366 Patch LGTM, r=me 968826 6 berto 2014-01-16 11:19:42 -0800 Committed r162137: <http://trac.webkit.org/changeset/162137> 968908 7 David.Ronis 2014-01-16 13:39:43 -0800 I just finished my build with the patch, it worked (Note: I still had -frename-registers in my CFLAGS/CXXFLAGS) Thanks 221366 2014-01-16 04:39:04 -0800 2014-01-16 08:47:51 -0800 Patch 126985.diff text/plain 1127 berto ZGlmZiAtLWdpdCBhL1NvdXJjZS9XVEYvQ2hhbmdlTG9nIGIvU291cmNlL1dURi9DaGFuZ2VMb2cK aW5kZXggMjc0ZDg2Yi4uNDliYWExNSAxMDA2NDQKLS0tIGEvU291cmNlL1dURi9DaGFuZ2VMb2cK KysrIGIvU291cmNlL1dURi9DaGFuZ2VMb2cKQEAgLTEsMyArMSwxNiBAQAorMjAxNC0wMS0xNiAg QWxiZXJ0byBHYXJjaWEgIDxiZXJ0b0BpZ2FsaWEuY29tPgorCisgICAgICAgIFNvdXJjZS9XVEYv d3RmL0F0b21pY3MuaDozMDA6IEVycm9yOiBiYWQgcmVnaXN0ZXIgbmFtZSBgJWJwbCcKKyAgICAg ICAgaHR0cHM6Ly9idWdzLndlYmtpdC5vcmcvc2hvd19idWcuY2dpP2lkPTEyNjk4NQorCisgICAg ICAgIFJldmlld2VkIGJ5IE5PQk9EWSAoT09QUyEpLgorCisgICAgICAgIFVzZSB0aGUgJ3EnIGNv bnN0cmFpbnQgdG8gZm9yY2UgdXNpbmcgYSByZWdpc3RlciB0aGF0IGFsbG93cworICAgICAgICBh Y2Nlc3MgdG8gaXRzIGxvd2VyIGJ5dGUuCisKKyAgICAgICAgKiB3dGYvQXRvbWljcy5oOgorICAg ICAgICAoV1RGOjp3ZWFrQ29tcGFyZUFuZFN3YXApOgorCiAyMDE0LTAxLTE1ICBBbGJlcnRvIEdh cmNpYSAgPGJlcnRvQGlnYWxpYS5jb20+CiAKICAgICAgICAgW0dUS10gdjIuMy4zIGZhaWxzIHRv IGJ1aWxkIGluIERlYmlhbiAvIEZyZWVCU0QKZGlmZiAtLWdpdCBhL1NvdXJjZS9XVEYvd3RmL0F0 b21pY3MuaCBiL1NvdXJjZS9XVEYvd3RmL0F0b21pY3MuaAppbmRleCBlNDAxMWFiLi44Mjk2MGY5 IDEwMDY0NAotLS0gYS9Tb3VyY2UvV1RGL3d0Zi9BdG9taWNzLmgKKysrIGIvU291cmNlL1dURi93 dGYvQXRvbWljcy5oCkBAIC0yOTUsNyArMjk1LDcgQEAgaW5saW5lIGJvb2wgd2Vha0NvbXBhcmVB bmRTd2FwKHVpbnQ4X3QqIGxvY2F0aW9uLCB1aW50OF90IGV4cGVjdGVkLCB1aW50OF90IG5ld1YK ICAgICAgICAgImxvY2s7IGNtcHhjaGdiICUzLCAlMlxuXHQiCiAgICAgICAgICJzZXRlICUxIgog ICAgICAgICA6ICIrYSIoZXhwZWN0ZWQpLCAiPXEiKHJlc3VsdCksICIrbSIoKmxvY2F0aW9uKQot ICAgICAgICA6ICJyIihuZXdWYWx1ZSkKKyAgICAgICAgOiAicSIobmV3VmFsdWUpCiAgICAgICAg IDogIm1lbW9yeSIKICAgICAgICAgKTsKICAgICByZXR1cm4gcmVzdWx0Owo=