Bug 1796046

Created attachment 1656254 [details]
The patch that makes the package build

Description of problem:

clang fails mass rebuild on ppc64le:
https://koji.fedoraproject.org/koji/taskinfo?taskID=41137358

build.log says:

../lib/Lex/Lexer.cpp: In member function 'bool clang::Lexer::SkipBlockComment(clang::Token&, const char*, bool&)':
../lib/Lex/Lexer.cpp:2545:34: error: ISO C++ forbids declaration of 'type name' with no type [-fpermissive]
 2545 |              !vec_any_eq(*(const vector unsigned char*)CurPtr, Slashes))
      |                                  ^~~~~~

Version-Release number of selected component (if applicable):

clang-9.0.1-3.fc32

How reproducible:

Always

Steps to Reproduce:
1. Rebuild clang for rawhide ppc64le (using gcc 10)

Actual results:

Failed build

Expected results:

Successful build

Additional info:

The following patch makes the build work:

$ cat clang-altivec-vector.patch 
diff -ur clang-9.0.1.src.orig/lib/Lex/Lexer.cpp clang-9.0.1.src/lib/Lex/Lexer.cpp
--- clang-9.0.1.src.orig/lib/Lex/Lexer.cpp	2019-12-11 20:15:30.000000000 +0100
+++ clang-9.0.1.src/lib/Lex/Lexer.cpp	2020-01-29 12:57:36.849173552 +0100
@@ -2542,7 +2542,7 @@
         '/', '/', '/', '/',  '/', '/', '/', '/'
       };
       while (CurPtr+16 <= BufferEnd &&
-             !vec_any_eq(*(const vector unsigned char*)CurPtr, Slashes))
+             !vec_any_eq(*(const __vector unsigned char*)CurPtr, Slashes))
         CurPtr += 16;
 #else
       // Scan for '/' quickly.  Many block comments are very large.

Koji scratch build: https://koji.fedoraproject.org/koji/taskinfo?taskID=41195794

I.e. changing vector to __vector

I can not say if this in an intentional change in gcc 10 or an unintentinal regression.