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/pubkey/dl_group/dl_group.cpp b/src/lib/pubkey/dl_group/dl_group.cpp
index 8e9c35f2a..ed9b60c7c 100644
--- a/src/lib/pubkey/dl_group/dl_group.cpp
+++ b/src/lib/pubkey/dl_group/dl_group.cpp
@@ -314,7 +314,7 @@ BigInt DL_Group::make_dsa_generator(const BigInt& p, const BigInt& q)
    const BigInt e = (p - 1) / q;
 
    if(e == 0 || (p - 1) % q > 0)
-      throw std::invalid_argument("make_dsa_generator q does not divide p-1");
+      throw Invalid_Argument("make_dsa_generator q does not divide p-1");
 
    for(size_t i = 0; i != PRIME_TABLE_SIZE; ++i)
       {