diff --git a/.github/workflows/coverage.yml b/.github/workflows/coverage.yml
index 8ead035d5..6ffd89978 100644
--- a/.github/workflows/coverage.yml
+++ b/.github/workflows/coverage.yml
@@ -40,8 +40,9 @@ jobs:
 
       - name: Install PySCIPOpt
         run: |
-          export CFLAGS="-O0 -ggdb" # disable compiler optimizations for faster builds
-          python -m pip install .
+          export CFLAGS="-O0 -ggdb -Wall -Wextra -Werror" # Debug mode. More warnings. Warnings as errors.
+          python -m pip install . -v 2>&1 | tee build.log
+          grep -i "warning" build.log || true
 
       - name: Run pyscipopt tests
         run: |
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4d44eda6c..ce0a27178 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@
 - Generalized getLhs() and getRhs() to additionally support any linear type constraint
 ### Fixed
 - Raised an error when an expression is used when a variable is required
+- Fixed some compile warnings
 ### Changed
 - MatrixExpr.sum() now supports axis arguments and can return either a scalar or MatrixExpr depending on the result dimensions
 ### Removed
diff --git a/src/pyscipopt/event.pxi b/src/pyscipopt/event.pxi
index 914e882ed..559d8c44a 100644
--- a/src/pyscipopt/event.pxi
+++ b/src/pyscipopt/event.pxi
@@ -39,7 +39,7 @@ cdef class Eventhdlr:
 
 
 # local helper functions for the interface
-cdef Eventhdlr getPyEventhdlr(SCIP_EVENTHDLR* eventhdlr) noexcept with gil:
+cdef Eventhdlr getPyEventhdlr(SCIP_EVENTHDLR* eventhdlr):
     cdef SCIP_EVENTHDLRDATA* eventhdlrdata
     eventhdlrdata = SCIPeventhdlrGetData(eventhdlr)
     return <Eventhdlr>eventhdlrdata
diff --git a/src/pyscipopt/expr.pxi b/src/pyscipopt/expr.pxi
index 563c73d4a..2fc56f5cb 100644
--- a/src/pyscipopt/expr.pxi
+++ b/src/pyscipopt/expr.pxi
@@ -358,7 +358,7 @@ cdef class ExprCons:
     def __repr__(self):
         return 'ExprCons(%s, %s, %s)' % (self.expr, self._lhs, self._rhs)
 
-    def __nonzero__(self):
+    def __bool__(self):
         '''Make sure that equality of expressions is not asserted with =='''
 
         msg = """Can't evaluate constraints as booleans.
diff --git a/src/pyscipopt/scip.pxd b/src/pyscipopt/scip.pxd
index 175c062e5..7059a9f3c 100644
--- a/src/pyscipopt/scip.pxd
+++ b/src/pyscipopt/scip.pxd
@@ -408,12 +408,6 @@ cdef extern from "scip/scip.h":
     ctypedef struct SCIP_PROPDATA:
         pass
 
-    ctypedef struct SCIP_PROPTIMING:
-        pass
-
-    ctypedef struct SCIP_PRESOLTIMING:
-        pass
-
     ctypedef struct SCIP_PRESOL:
         pass
 
@@ -456,9 +450,6 @@ cdef extern from "scip/scip.h":
     ctypedef struct SCIP_PRESOL:
         pass
 
-    ctypedef struct SCIP_HEURTIMING:
-        pass
-
     ctypedef struct SCIP_SEPA:
         pass
 
@@ -510,9 +501,6 @@ cdef extern from "scip/scip.h":
     ctypedef struct BMS_BLKMEM:
         pass
 
-    ctypedef struct SCIP_EXPR:
-        pass
-
     ctypedef struct SCIP_EXPRHDLR:
         pass
 
@@ -708,7 +696,6 @@ cdef extern from "scip/scip.h":
     SCIP_Real SCIPgetLocalTransEstimate(SCIP* scip)
 
     # Solve Methods
-    SCIP_RETCODE SCIPsolve(SCIP* scip)
     SCIP_RETCODE SCIPsolve(SCIP* scip) noexcept nogil
     SCIP_RETCODE SCIPsolveConcurrent(SCIP* scip)
     SCIP_RETCODE SCIPfreeTransform(SCIP* scip)
diff --git a/src/pyscipopt/scip.pxi b/src/pyscipopt/scip.pxi
index cdedebe83..26abf8c29 100644
--- a/src/pyscipopt/scip.pxi
+++ b/src/pyscipopt/scip.pxi
@@ -7974,7 +7974,6 @@ cdef class Model:
 
         """
         raise Warning("model.getDualMultiplier(cons) is deprecated: please use model.getDualsolLinear(cons)")
-        return self.getDualsolLinear(cons)
 
     def getDualfarkasLinear(self, Constraint cons):
         """