Reroot the exception hierarchy into a toplevel Exception class

As the alternatives are unfortunate for applications trying to catch
all library errors, and it seems deriving from std::runtime_error
causes problems with MSVC DLLs (GH #340)

Effectively reverts 2837e915d82e43

1 files changed, 1 insertions, 1 deletions

diff --git a/src/lib/math/bigint/big_io.cpp b/src/lib/math/bigint/big_io.cpp
index 3e66f788d..779f8ccb7 100644
--- a/src/lib/math/bigint/big_io.cpp
+++ b/src/lib/math/bigint/big_io.cpp
@@ -19,7 +19,7 @@ std::ostream& operator<<(std::ostream& stream, const BigInt& n)
    if(stream.flags() & std::ios::hex)
       base = BigInt::Hexadecimal;
    else if(stream.flags() & std::ios::oct)
-      throw std::runtime_error("Octal output of BigInt not supported");
+      throw Exception("Octal output of BigInt not supported");
 
    if(n == 0)
       stream.write("0", 1);