Build error with protobuf branch 3.10.x

[cwlseu]

CXX google/protobuf/text_format.lo
google/protobuf/text_format.cc: In member function ‘virtual void google::protobuf::TextFormat::FastFieldValuePrinter::PrintFloat(float, google::protobuf::TextFormat::BaseTextGenerator*) const’:
google/protobuf/text_format.cc:1623:27: error: ‘__builtin_isnan’ is not a member of ‘std’
generator->PrintString(!std::isnan(val) ? SimpleFtoa(val) : "nan");
^
google/protobuf/text_format.cc:1623:27: note: suggested alternative:
: note: ‘__builtin_isnan’
google/protobuf/text_format.cc: In member function ‘virtual void google::protobuf::TextFormat::FastFieldValuePrinter::PrintDouble(double, google::protobuf::TextFormat::BaseTextGenerator*) const’:
google/protobuf/text_format.cc:1627:27: error: ‘__builtin_isnan’ is not a member of ‘std’
generator->PrintString(!std::isnan(val) ? SimpleDtoa(val) : "nan");
^
google/protobuf/text_format.cc:1627:27: note: suggested alternative:
: note: ‘__builtin_isnan’
Makefile:4019: recipe for target 'google/protobuf/text_format.lo' failed
make[1]: *** [google/protobuf/text_format.lo] Error 1
make[1]: Leaving directory '/home/xxxx/Repo/graph-learn/third_party/protobuf/protobuf/src'
Makefile:1723: recipe for target 'install-recursive' failed
make: *** [install-recursive] Error 1

[cwlseu]

I have fix the compile error with the solution following, but I don't know why the two line result to the compile error, anyone know why? thanks.

diff --git a/src/google/protobuf/text_format.cc b/src/google/protobuf/text_format.cc
index 8fc197a..be8231d 100644
--- a/src/google/protobuf/text_format.cc
+++ b/src/google/protobuf/text_format.cc
@@ -35,7 +35,7 @@
 #include <google/protobuf/text_format.h>

 #include <float.h>
-#include <math.h>
+#include <cmath>
 #include <stdio.h>

 #include <algorithm>

or update deps https://github.com/protocolbuffers/protobuf/tree/3.11.x

[jackonan]

Your OS and g++ version? It seems some error with your environment. Try to just build protobuf from source code may be a help.

[cwlseu]

My OS is ubuntu 16.04 and g++ version is 5.4. The g++ version is build from source and In my system installed g++-4.9 & g++-5.5 concurrently. I think the problem may result from complex compiler envirnment. The problem isn't exist in a pure ubuntu16.04 with gcc 5.4 envirnment. Thanks.